# C Program to find prime number

**What is prime number?**

**Definition of prime number**

- A number is considered as prime number when it satisfies the below conditions.It should be whole number
- It should be greater than 1
- It should have only 2 factors. They are, 1 and the number itself.

**For Example:**

2, 3, 5, 7, 11, 13, 17, 19, 23, 29 etc

## Let us see the C program below:

#include <stdio.h>

int main()

{

int i, num, p = 0;

printf(“Please enter a number: \n”);

scanf(“%d”, &num);

for(i=1; i<=num; i++)

{

if(num%i==0)

{

p++;

}

}

if(p==2)

{

printf(“Entered number is %d “\

“and it is a prime number.”,num);

}

else

{

printf(“Entered number is %d “\

“and it is not a prime number.”,num);

}

}

**Output:**

Please enter a number: 17

Entered number is 17 and it is a prime number.

Entered number is 17 and it is a prime number.

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