Num2Time(n [,f [, k ]])
n
If n is invalid, the function returns an error.
f (Optional)
A time format string. If you do not include a value for f, the function uses the default time format H:MM:SS A.
k (Optional)
A locale identifier string that conforms to the locale naming standards. If you do not include a value for k, or if k is invalid, the function uses the ambient locale.
The function returns a value of 0 if any of the following conditions are true:
00:00:00 in Greenwich, England and 09:00:00 in Tokyo.
13:13:13 EST in Boston, U.S.
13:13:13 GMT-05:00 to a German-Swiss user in Boston, U.S.
13.13 Uhr GMT+01:00 to a user in Zurich, Austria.
13:13+01:00 to a user in Zurich, Austria.

Num2Time