In this C program, we will calculate all prime factors of a number. A Prime Factor of a number is a factor that is also a prime number.
A Prime number is a natural number greater than 1 that is only divisible by either 1 or itself.

For Example: Prime factors of 15 are 3 and 5.

#### Required Knowledge

- C printf and scanf functions
- For loop in C
- C Program to find factors of a number
- C program to check prime numbers

## C program to print all prime factors of a number using for loop

#include <stdio.h> int main() { int counter, N, i, isPrime; printf("Enter a Number\n"); scanf("%d", &N); printf("List of Prime Factors of %d\n", N); for(counter = 2; counter <= N; counter++) { if(N%counter==0) { isPrime = 1; for(i = 2; i <=(counter/2); i++) { if(counter%i==0) { isPrime=0; break; } } if(isPrime==1) printf("%d ", counter); } } return 0; }Output

Enter a Number 15 List of Prime Factors of 15 3 5

Enter a Number 50 List of Prime Factors of 50 2 5

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