Examples
?- convert_time(0, X).
X = 1970-01-01T00:00:00.000+0000
yes
?- convert_time(0, '1970-01-01T00:00:00.000+0000').
yes
?- convert_time(1000*60*60*24*500+(1000*60*72), X).
X = 1971-05-16T01:12:00.000+0000
yes
?- convert_time(1000*60*60*24*500+(1000*60*72), '1971-05-16T01:12:00.000+0000').
yes
?- convert_time(9223372036854775807, X).
X = 292278994-08-17T07:12:55.807+0000
yes