Not sure if you can use this but if you simply want to convert that to a readable date, you can use:
date -d @1440604784 +'%d.%m.%Y'
The output would be:
26.08.2015
i think you have to multiply the Unix time by 1000 because Unix time is in Seconds but the "date" takes milliseconds.
also the output should also contain time 08/26/2015 @ 3:59pm