It's much simpler to do this:
DateTime dt = new DateTime(633896886277130000);
Which gives
dt.ToString() ==> "9/27/2009 10:50:27 PM"
You can format this any way you want by using dt.ToString(MyFormat)
. Refer to this reference for format strings. "MMMM dd, yyyy"
works for what you specified in the question.
Not sure where you get October 1.