34. Check Prime Number

using System;
using System.Numerics;

public class CheckPrimeNumber
{
    static void Main()
    {
        BigInteger n = BigInteger.Parse(Console.ReadLine());
        if (n < 2)
        {
            Console.WriteLine("Not Prime");
            return;
        }

        for (long i = 2; i < (long)Math.Floor(Math.Sqrt(double.Parse(n.ToString()))); i++)
        {
            if (n % i == 0)
            {
                Console.WriteLine("Not Prime");
                return;
            }
        }

        Console.WriteLine("Prime");
    }
}