Convert Seconds to HH:MM:SS

Int64 Yourseconds = 19800;
TimeSpan spanTM = new TimeSpan(TimeSpan.TicksPerSecond * Yourseconds);
string TimeStr = spanTM.Hours.ToString("00") + ":" + spanTM.Minutes.ToString("00") + ":" + spanTM.Seconds.ToString("00");
Response.Write(TimeStr);