The following program will help you to find the

**largest prime factor**of a number. If you want to know know about prime factors you may visit this post by me.
Here is the C Program:

#include <stdio.h> int main() { long long number; printf("Enter a number to know its largest prime factor: "); scanf("%lld",&number); long long div=2, ans = 0, maxFact; while(number!=0){ if(number % div !=0) div = div + 1; else{ maxFact = number; number = number / div; if(number == 1){ printf("%d is the largest prime factor !",maxFact); ans = 1; break; } } } return 0; }