using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Prime Number");

        Console.WriteLine("Enter a number");

        int num = int.Parse(Console.ReadLine());

        int counter = 1 ;

        int counter2 = 0 ;

        while (counter <= Math.Sqrt(num))

        {

            if(num % counter == 0)

            {

                counter2++;

            }

            counter++;

        }

        if (counter2 == 1)

        {

            Console.WriteLine("It is a prime number");

        }

        else

        {

            Console.WriteLine("It is not a prime number");

        }

    }

}