#include <iostream>
using namespace std;

int main() {

    // write your code here......
    int digit = 0;
    int flag = 0;
    cin >> digit;
    if (2 == digit)
    {
        cout << "是质数";
    }
    else
    {
        for (int i = 2; i < digit; i++)
        {
            if (digit % i == 0)
            {
                //
                flag = 1;
                break;
            }
            else
            {
                //cout << "是质数";
                continue;
            }
        }

        if (1 == flag)
        {
            cout << "不是质数";
        }
        else
        {
            cout << "是质数";
        }
    }
    return 0;
}