Program for Number is Prime or Not in C#

namespace prime_or_not
{
    class Program
    {
        static void Main(string[] args)
        {
            int numb, temp = 0;
            Console.WriteLine("Enter a number.");
            numb = Convert.ToInt32(Console.ReadLine());
            for (int i = 1; i <= numb; i++)
            {
                if (numb % i == 0) temp++;
            }
            Console.WriteLine(temp);
            if (temp == 2) Console.WriteLine("Is a prime");
            else Console.WriteLine("Not a prime");
            Console.ReadKey();
        }
    }
}