Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

What are Even, Odd, Prime and Composite Numbers

ffImage
Last updated date: 27th Apr 2024
Total views: 551.4k
Views today: 15.51k
hightlight icon
highlight icon
highlight icon
share icon
copy icon

Introduction

There are, as I'm very sure that you recognize, tons of numbers, infinitely several because it happens. Because of this mathematicians need a way to classify numbers or integers, a way to group them and tell them apart from each other. In this unit, we are attempting to examine the various teams of numbers that exist.


Natural Numbers – or the count numbers – are in all probability the primary style of numbers you'll have bumped into since you have learned to count. The Natural numbers are unit whole numbers larger than zero. These numbers include 1, 2, 3, 4, …, basically, they are the numbers that can be physically counted. Natural Numbers do not include negative values.


Now depending on the divisible property, all the natural numbers can be broadly classified into four types. These are:


i) Even Numbers

ii) Odd Numbers

iii) Prime Numbers

iv) Composite Numbers


In the consequent sections, we will try to understand the property and the functionality of each of these numbers. Identifying even and odd numbers is a crucial ability that will help youngsters in their preparation to group whole number operations as well. It will also be of great use while they will start learning division, prime numbers, and even square root.


Even Numbers

Any integer that can be divided exactly by 2 with no remainders is an even number. The last digit of the number will essentially be 0, 2, 4, 6, or 8. This means that the integer may be divided into pairs or 2 equal parts with no leftovers. The numbers 2, 4, 6, 8, and 10 are considered even numbers.


Please note that zero is considered an even number. So, any number ending with 0 will be an even number by default.


Odd Numbers 

An odd integer isn't divided equally by 2. An odd integer can't be divided into pairs or 2 equal numbers while having no leftovers. an odd number could be an integer that contains a remainder of one upon division by two. The last digit will essentially be 3,5,7 and 9. The numbers 1, 3, 5, 7, and 9 all are considered odd numbers. Odd numbers are in between the even numbers and vice versa.


Let’s Try Something: 

What are the common characteristics shared by all even numbers?


What are the common characteristics do all odd numbers have?


How can you identify whether a number is odd or even using the method of skip counting?


Prime Numbers

A prime integer may be a number larger than 1 that has no positive number divisors aside from 1 and itself. For example, 5 is a prime number as it has no positive divisors other than 1 and 5.


The first few prime numbers include 3, 5, 7, 11, 13, 17,...


Prime numbers have applications in basically all areas of arithmetic. Prime numbers act as "building blocks" of numbers, and in and of itself, it's vital to know prime numbers in order to understand how numbers are associated with one another.


Composite Numbers

Contrary to the prime numbers, a number may be a positive whole number larger than 1 that has two or more positive divisors. For example, 6 may be a number as a result of its 4 positive divisors: 1, 2, 3, and 6. All positive integers larger than 1 should either be a prime integer or a composite one. 1 is that the solely positive whole number that's neither prime nor composite.


(Image will be uploaded soon)


Some Interesting Facts

Adding and Subtracting:

Results of the Addition or Subtraction of Odd or Even Numbers Follow a Pattern


Even + Even

= Even

6 + 8 = 14

Even + Odd

= Odd

4 + 3 = 7

Odd + Even

= Odd

9 + 10 = 19

Odd + Odd

= Even

5 + 7 = 2


Similarly, when subtraction is performed, the similar pattern is observed.


Multiplying:

Multiplication of Two Odd/Even Numbers Will Always Give an Even Number as Output


Even × Even

= Even

6 × 8 = 48

Even × Odd

= Even

2 × 5 = 10

Odd × Even

= Even

5 × 8 = 40

Odd × Odd

= Odd

9 × 7 = 63


Division:

As you'll be able to see, there are a couple of rules that can tell the result after you will add, subtract, or multiply even and odd numbers. In any of those operations, you may continually get a selected quiet integer. But after you divide numbers, one thing tough will happen - You may well be left with a fraction. Fractions are neither even numbers nor odd numbers, thus they are not whole numbers as well. They are solely components of numbers and might be written in numerous ways that. For example, you cannot say that the fraction 1/5 is odd as a result of the divisor being an odd number. You could even as well write that very same fraction as 2/10, during which the divisor is an even one.


The terms “even number” and “odd number” are solely used for whole numbers and their opposites.


Identify it To tell whether or not a number is even or odd, scrutinize the digit within the one’s/unit’s place. That single variety can tell you whether the whole number is odd or even. Consider the number 98765. It ends in 5, an odd number. Therefore, it is an odd number. Likewise, 424 is an even number as the digit in the unit’s place is an even one. The simplest way to establish whether a number is a prime number or not is to use the method of elimination. List out numbers, eliminate those having a primary divisor that's not the number itself, and the remaining numbers will be prime.


Identify it

To tell whether or not a number is even or odd, scrutinize the digit within the one’s/unit’s place. That single variety can tell you whether the whole number is odd or even. Consider the number 98765. It ends in 5, an odd number. Therefore, it is an odd number. Likewise, 424 is an even number as the digit in the unit’s place is an even one.


The simplest way to establish whether a number is a prime number or not is to use the method of elimination. List out numbers, eliminate those having a primary divisor that's not the number itself, and the remaining numbers will be prime.


Another Way to Spot Prime Numbers is as follows:


First, choose a number, for example, 113. Now, note that prime numbers between 1 and 10 are 2, 3, 5, 7. Now, divide the chosen number 113 by each of these four numbers. If it's divisible by any of the four numbers, then it isn't a prime number; if it's not divisible by any of the four numbers, then it is prime.113 is not divisible by any of them, so it is a prime number.


The best way to puzzle out if it’s a prime number is to perform the quality check. To do this, you must check to check if the given number is divided by these common factors: a pair of, 3, 5, 7, 11, and 13. If the integer is even, then begin with the divisibility by 2. If the number ends with a 0 or 5, attempt dividing by 5. If the number can’t be divided by any of those six numbers, then the number is most likely a prime number.


Test Your Skills with the Divisibility Test with the Following Examples:


243: 

Since the number ends with a 3, we all know that it won’t fall under even numbers. Therefore, it’s not divisible by 2. Also, it doesn’t finish with a 0 or 5, therefore it isn’t a multiple of 5 either. So, we will move on to the consequent lowest number: 3.


243/3 = 81 


Since the given number has more than two factors, we know that it’s a composite number. The factors of 243 include 1, 3, 81, 27, 81, 243 (1 × 243, 3 × 81, 9 × 27).


283:

As we have a tendency to perform the quality check with 283, we find that


283/2 = 141.5


283/3 = 94.33


283/5 = 56.6


283/7 = 40.43


283/11 = 25.72


283/13 = 21.76


Since none of the quotients measures whole numbers, we will with confidence say that 283 could be a prime.


Some Fun Activities

  1. Find out if 678 is an odd or even number. Find and explain if 1500 is an odd or even number.
  2. If we multiply the digits 6 and 5 the result is even because the result ends in 0. Similarly, if we multiply two odd nos. like 3 and 5, the result is odd as the result ends with 5.
  3. Now find out how many 2-digit numbers have an odd product?
  4. Complete the following sequence till 31: 2,5,7,11…
  5. Find out the sum of the two largest two-digit prime numbers?
  6. Is the number 9 prime or composite? Write down the prime numbers between 60 and 69.
  7. State true or false: Every number is a multiple of 1.
  8. Write a composite number that is less than 10 and is also an odd number.
  9. Which is the even yet prime number 2, 4, 6, 8,.... are examples of the _________ of 2.
  10. Pick up the true statement about the number 


231. 

More than one answer can be true.


(a) It is an odd number.

(b) It is an even number.

(c) None of the above.

(d) It is a prime number.

(e) It is a composite number.

(f) Neither composite nor prime.


Prime Numbers:

These numbers are classified into categories that consist of a whole number that has exactly two integral divisors. This includes one and the number itself.


Composite Number:

These numbers are classified into categories that contain more than two integral divisors.


It is found that except for the numbers 0 and 1 all the whole numbers present in the number system is either prime or composite.


How to Find a Number that is Prime or Composite?

There are some of the basic criteria which you should take care of when you are differentiating between a prime number and a composite number. These criteria can be defined as described below:


  • Any number which is integrated into or is a multiple of 2 cannot be prime as that particular number will hold a divisor which is 2. It also suggests that every even number is non-prime

  • The next criteria which we should look upon are the divisibility test of the numbers


  • Divisibility Test for 2:

Numbers that are divided by 2 leave no remainder is divisible with 2 and hence they are non-prime.


  • Divisibility Test of 3:

Add all the numbers given and if the following sum is divisible by 3 then the number is considered to be divisible with 3 and hence becomes non-prime.


  • Divisibility Test for 5:

If the given number has a 5 or a 0 at the end then it is divisible with 5 making it again a non-prime number.

  • Coming to the divisibility test for 7 and 1, it doesn't go evenly. So, you can say that it's prime as it will have only two divisors that will be 1 and the number itself.


Applications of Prime and Composite Numbers:

Prime and composite numbers are used in a used range of criteria and this can be listed as below:


  • Engineering

  • Architecture ( designing gears and avoiding patterns that arrive at random series.

  • Bank accounts for making codes that are prime are known by the bank only.

  • Asymmetric cryptography

  • To reassure equal wear of cogwheels and avoid resonance

FAQs on What are Even, Odd, Prime and Composite Numbers

1. Is zero a prime number, composite number, even number, or odd number?

Even numbers are the numbers that are divisible with 2 . As 0 is divisible with 2, it is an even number. 


Odd numbers are the numbers that are divisible with 2 when added with 1 . So, (0+1) gives rise to 1, which when divided by 2, leaves a remainder 1. So,0 is not an odd number.


Prime numbers are nos that have only two factors, 1 and the number itself. 0 is divisible with every number and has infinite factors, so it is not a prime number. 


Composite numbers are obtained by multiplying two smaller positive integers. Since there is no positive integer less than 0, so, it is not a composite number.

2. What are even, odd, or prime types?

Finally, the number which contains only two factors i.e., 1 and the number itself is termed as a prime number.

3. Are all prime numbers odd?

The criteria which a prime number satisfies is that it should not get divisible with more than 2 numbers that are too with 1 and the number itself. So, except for 2, all odd numbers are considered prime numbers. This is because every even number is divisible by 2, preventing it from being a prime number.

4. What is a real number?

Real numbers include almost all types of numbers combined as rational as well as irrational. The rational numbers are summed up as integers, fractions, etc. Irrational numbers sum up √3,√4, algebraic numbers, etc. It is denoted by 'R'. It can be simply defined as an infinite decimal expansion or a number line that denotes a continuous quantity.

5. How do you know if a number is real or not?

An old trick that has been found very well before is still used in order to identify real numbers. The trick is a number line. Think of a horizontal line, where the origin is taken as zero (0).


Even numbers are defined as the numbers which are divisible by 2. These are represented as(2n). Odd numbers are defined as the numbers which are divisible with 2 when added with or subtracted with 1. It is generally denoted by (2n-1) or (2n+1). And number line includes all the positive numbers on the right side and the left side includes all the negative numbers.