# Prime Numbers Definition

Jan 22, 2023

This post contains the funs and facts of Prime Numbers, Composite Numbers, Co-prime Numbers and important Question-Answers for all competitive viewers and New children who try to know the mathematics in easy way.

###### Prime Number:

Prime Numbers are the selective natural numbers that are divisible by one (1) and itself. Each and every prime number has only two factors one and itself. Prime numbers are positive natural number. 1 is not a prime number.

Prime Number: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, ………

###### Magical funs and facts of prime numbers:
• 1is not a prime number but it is a natural number and whole number.
• 2 is the smallest prime number and even prime number.
• Except 2, all prime numbers are odd prime numbers.
• Every two prime numbers are always co-prime numbers of each other.
• All 25 prime numbers between 1 and 100.
• All 15 prime numbers between 1 and 50.
• All 10 prime numbers between 50 and 100.
• Only two consecutive natural numbers are prime number i.e. 2 and 3.
###### How to find the prime numbers?

Prime Numbers are the multiple of 6 and either add 1 or subtract 1.

Here, 6n+1

Rule: To check a number is a prime number or not?

We get a number 503.

503 + 1= 504; Either 504 is divisible by 6, then it is a prime number

Or

503 – 1 = 502; 502 is divisible by 6, then it is a prime number

So, 504 is divisible by 6. Hence, 503 is a prime number

###### Composite Number:

Composite Numbers are the natural numbers that have more than two factors are called the composite numbers. Composite Numbers must have at least one more factor except 1 and itself. 1, 2 and 3 are not a composite number.

Composite Number: 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21,…………

###### Co-prime Number:

Co-prime Numbers are always in a pair that have only one common factor for both. A pair of numbers are said to be co-prime number that have highest common factor (HCF) is 1. Each number of a pair is the co-prime number of other number. Co-prime Number: (2,3), (3,5), (5,7), (1,2), (5,6), (4,9), (3,10), (3,11)…….

###### Lets do some fun with prime numbers and co-prime numbers?

Q: To check the following numbers are prime numbers or not?

###### Q: To check the following pairs are co-prime number or not?

For General Knowledge: General Knowledge || Decimal Number System