ACACACACACAC

#include <iostream>
using namespace std;
bool is_prime(int x){
    if(x <= 1) return false;
    else if(x == 2) return true;
    else{
        for(int i = 2; i < x; i++){
            if(x % i == 0) return false;
        }
    }
    return true;
}

int main(){

	int n;
	cin >> n;
	if(is_prime(n)) cout << "Yes" << endl;
	else cout << "No" << endl;
    
   return 0;
}