#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

int main()
{
    ll m, d;
    cin >> m >> d;
    ll x = m * 100 + d;
    for (int i = 2; i * i < x; ++i) {
        if (x % i == 0) {
            cout << "No" << endl;
            return 0;
        }
    }
    cout << "Yes" << endl;
}