find . -printf "%T@ %Tc %p\n" | sort -n
printf arguments from man find:
%Tk: File's last modification time in the format specified by k.
@: seconds since Jan. 1, 1970, 00:00 GMT, with fractional part.
c: locale's date and time (Sat Nov 04 12:02:33 EST 1989).
%p: File's name.