#include<iostream>
#include<sstream>
#include<cstdio>
#include<cstring>
#include<string>
#include<vector>
#include<list>
#include<queue>
#include<stack>
#include<utility>
#include <fstream>
#include<set>
#include<map>
#include<cctype>
#include<cmath>
#include<algorithm>
#include <numeric>
using namespace std;


#define RALL(x) (x).rbegin(),(x).rend()
#define ALL(x) (x).begin(),(x).end()
#define repp(i,n) for(int (i)=1;(i)<=(n);(i)++)
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define rev(i,n) for(int (i)=(n-1);(i)>=0;(i)--)
#define clr(a) memset((a), 0 ,sizeof(a))
#define found(s,e) ((s).find(e)!=(s).end())

typedef pair<int,int> P;
typedef vector<pair<int,int> > pii;
typedef map<string,int> mdi;


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

int main(){
	long long n;
	bool ok;
	cin >> n;
	ok=isprime(n);
	if(ok||n==1) cout << "NO" << endl;
	else cout << "YES" << endl;
	return 0;
}