php - 18 digit timestamp? -

I am working on a system related to TV recording.

I am parsing the following XML from one system (to which I have no documents):

My question is, does anyone know the timestamp format of startup and stoptime? I generally thought the timestamps for the second was 10 points, so where are the other 8 coming from? My guess is something like the time zone and millisecond accuracy.

I'm using php in a specific manner, but nothing is good so php would be good to change it to a datetime.

itemprop = "text">

It looks like the date time of C #:

this line:

  console Virline (new date time (633 9 836042047633656));  

Print:

2009/11/12 06:30:04

You have to convert Unix time, those 621355968000000000 L, which is the unix era expressed in ticks , those numbers needed.