https://www.e-olymp.com/az/problems/1616

/*
    Author: Kanan Asgarli
    https://www.e-olymp.com/az/problems/1616
*/
#include <iostream>
#include <cmath>
using namespace std;
int n;
string prime(){
    for(int i = 2; i <= (int)sqrt(n); i++)
        if(n % i == 0)
            return "No";
    return "Yes";
}
int main()
{
   cin>>n;
   cout<<prime()<<endl;
   return 0;
}