#include "stdafx.h"
#include <iostream>
using namespace std;
int main()
{
    int number, count = 0;
    cin >> number;

    for (int i=0; i < 32; i++)
    {
        count += (number >> i) & 1;
    }

    if(count == 1)
    {
        cout << "YES";
    }
    else
    {
        cout << "NO";
    }

    return 0;
}