#include<bits/stdc++.h>
using namespace std; 
#define int long long
#define rep(i,n) for(int i=0; i<n; i++)
#define repa(i,a,n) for(int i=a; i<n; i++)

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