Replaces the “#” symbol with the corresponding digit if one is present; otherwise, no digit appears in the result string.
Note that no digit appears in the result string if the corresponding digit in the input string is a non-significant 0. For example, 0003 (“####”) -> 3.
So in your case you have a six digit number but only three “#” symbols so it’s going to have no effect whatsoever.
If you had more “#”‘s or a smaller number, you’d see a difference.