You need to convert second to DateTime object
DateTime origin = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
origin.AddSeconds(timestamp);
After that, you can get hour, min, sec, etc... from DateTime object
var hour = origin.Hour;
var min = origin.Minute;
var sec = origin.Second;
for more information;
https://msdn.microsoft.com/tr-tr/library/system.datetime(v=vs.110).aspx[
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