In sms_stats_data.json it is recorded the session end time like this:

"stages" : {
          "race1" : {
            "end_time" : 1565158567,
I know this integer means 2019-08-07 05:06:57 (UTC), but I don't know how to parse it in my own app and convert it in datetime. What is this integer? at the begining I was believing it was total seconds from 01/01/1900, but I was wrong. Could anybody help me?

Thanks in advance.