tj

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

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