#include<iostream>
#include<cmath>

using namespace std;

int main(){

	long long N;

	cin>>N;

	double hani=sqrt((double)N);
	bool f=true;

	for(int i=2;i<hani;i++){
		if(N%2==0) f=false;
	}

	if(f||N==1) cout<<"NO"<<endl;
	else cout<<"YES"<<endl;
}