#include <stdio.h>
#include <math.h>
#include "euler.h"
#include "utils.h"

#define MAX 600851475143LL

int p3()
{
    long long largest = 0;
    for (long long i = 2; i <= sqrt(MAX); i++) {
        if (MAX % i == 0 && isprime(i))
            largest = i;
    }
    printf("%lld\n", largest);
    return 0;
}