#include <bits/stdc++.h>
using namespace std;

int main(){
    int M, D, N;
    cin >> M >> D;
    N = 100*M+D;

    bool ok = true;
    for (int p = 2; p*p <= N; p++){
        if (N%p == 0){
            ok = false;
        }
    }

    if (ok) cout << "Yes" << endl;
    else cout << "No" << endl;
}