Format the cell with a custom format. In the custom format box, type 0"s.
For example, if you wanted your cell to contain leading zeroes for an 8
digit string, you would type 00000000 (eight zeroes).
Possibilities I can think of:
1) To get fixed number of digits in a numerical result
(whole or decimal), format the cell as follows:
-choose custom and enter a custom format in the entry box
-enter e.g. 000.00 to make cell entry "44.2" appear
as "044.20"
-Once you enter this custom format, it is available from
the custom menu anytime in the future.
2) Enter e.g. " '003 " (apostrophe 003). This has to
be done on a cell-entry basis. That is, you type the
apostrophe every time you enter a value in the cell. Cell
math still works on data entered this way.