The following code shows how to Display All Prime Factors of a Number in C.

// Find Prime Factors of a Number

#include <stdio.h>

int main()
{
    int mynumber, i, j, prime=1, factor;
    printf("Enter a number: ");
    scanf("%d", &mynumber);
    printf("Prime Factors of the number %d are...\n", mynumber);
    for(i=2;i<=mynumber;i++){
        if(mynumber%i==0)
        {
            factor=i;
            for(j=2;j<=factor/2;j++)
            {
                if(factor%j==0)
                {
                    prime=0;
                    break;
                }
            }
            if(prime)
            {
                printf("%d ", factor);
            }
            prime=1;
        }
    }
    return 0;
}

Output

Enter a number: 329
Prime Factors of the number 329 are…
7 47

Further Reading

50+ C Programming Interview Questions and Answers

C Program to Find Factorial of a Number