DATE(My_Field,'DD-MM-YYYY HH:MM:SS') if your field holds the numeric value 41567 then it will return which is the date equivalent in the format you specified 20-10-2013 00:10:00.
Note the time format is : HH:MM:SS not HH:MI:SS
The exact result of what your function will give you as is: 30-12-1899 00:12I:00