Untitled

#include <iostream>
using namespace std;
int main()
{
	int a, i, summ = 0;
	cin >> a;
	for (i = 1; i < a+1; i++)
	{
		if (a % i == 0)summ += 1;

	}
	if (summ == 2) cout << "Yes";
	else cout << "No";
}