using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var x = new MyClass();

        Type t = typeof(MyClass);

        var pi = t.GetProperty("MyProp");

        Type pt = pi.GetType();

        Console.WriteLine("Property type ... {0}", pi);

        Type answer = Nullable.GetUnderlyingType(pi);

        Console.WriteLine("Underlying type ..... {0}", answer);

    }

    public class MyClass

    {

        public int? MyProp { get; set; }

    }

}