select cast(40147 as datetime); -- displays 2009-12-02 00:00:00.000
select cast(-53690 as datetime); -- displays smallest datetime value '1753-01-01'
select cast(getDate() as int); -- displays 40294
select getDate() + 1; -- displays tomorrows date same time

select getDate() + 1; 

select getDate() + cast(1 as datetime); -- 1 as datetime is '1900-01-02'

select getDate() + cast('1900-01-02' as datetime);