#include <bits/stdc++.h>
using namespace std;
int main(){
int n,i,s=0;
cin>>n;
for(i=2;i<n;i++){
if(n%i==0){
s=1;
cout<<i;
break;
}
}
if(s==0) cout<<"Yes";
}
/**************************************************************
Problem: 1061
User: fuyijun
Language: C++
Result: Accepted
Time:8 ms
Memory:2072 kb
****************************************************************/