#include<iostream>
#include<sstream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<string>
#include<vector>
#include<cmath>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<numeric>
#include<functional>
#include<complex>

using namespace std;
#define BET(a,b,c) ((a)<=(b)&&(b)<(c))
#define FOR(i,n) for(int i=0,i##_end=(int(n));i<i##_end;i++)
#define SZ(x) (int)(x.size())
#define ALL(x) (x).begin(),(x).end()
#define MP make_pair
#define FOR_EACH(it,v) for(__typeof(v.begin()) it=v.begin(),it_end=v.end() ; it != it_end ; it++)
typedef vector<int> VI;
typedef vector<VI> VVI;

bool solve(long long N){
    if(N == 1) return true;
    for(int i=2;1LL*i*i<=N;i++){
        if(N % i == 0) return true;
    }
    return false;
}

int main()
{
    long long N;
    cin>>N;
    puts(solve(N)?"YES":"NO");
    return 0;
}