How to check whether N is a prime number?

Let’s play with prime

Wait…….!

What is a Prime number?

A prime number is a whole number which is only divisible by the 1 and the number itself.

Let’s see the conversation between prime numbers and consonant numbers.

Prime number: Hey..! consonant number.

Consonant number: Hey..! prime number. Can you tell who can divide you?

Prime number: The first natural number ‘1’ can divide me.

Consonant number: Wow! ‘1’ can divide me also. Can any other divide you?

Prime number: Not possible…….. Other than ‘1’ only I can divide my self.

Consonant number: That’s Great… Ok Bye … Prime number.

Prime Number: Bye..!

Procedure to check Prime Number

STEP 1: Return False, if N = 0 or N = 1

STEP 2: Return True, if N = 2 or N = 5

STEP 3: Return False, if unit digit of N is ‘5’ or ‘0’. Use Bitwise operators to reduce calculation complexity.

STEP 4: Return False, if N is an Even Number.

STEP 5: Take the square root of N. If any of the prime numbers less than or equal to the Square root of N divides N properly, then return False. Else return True.

Python Program

C Program

Hurray…! Hope it will help you.