#include <iostream>
using namespace std;

unsigned long long n;

int main()
{
	cin >> n;

	int r = 0;
	for ( unsigned long long i = 2; !r && i * i <= n; i++ ) {
		r = n % i == 0;
	}

	cout << (r ? "YES" : "NO") << endl;

	return 0;
}