Calculate Factorial Number with Iterative using C# dotnet

 class factorial6  
   {  
     public static void Main()  
     {  
       Console.WriteLine("4! = {0}", Math.Factorial(4));  
       Console.ReadLine();  
     }  
   }  
   class Math  
   {  
     public static long Factorial(long number)  
     {  
       long factorial = 1;  
       for (long i = number; i >= 1; i--)  
       {  
         factorial *= i;  
       }  
       return factorial;  
     }  
   }