#include <iostream>

using namespace std;

#define loop(i,a,b) for(int i=(a);i<int(b);i++)
#define rep(i,b) loop(i,0,b)

typedef long long ll;

bool isp(ll n){
    if (n == 1) return true;
    for (ll i = 2; i*i <= n; i++){
        if (n%i == 0) return false;
    }
    return true;
}

int main(){
    ll N; 
    while (cin >> N){
        cout << (isp(N) ? "NO" : "YES") << endl;
    }
}