Numbers in the form of 001

Question

Is there a special name for numbers in the format of 001. For example the number 20 would be 020 and 1 would be 001.
Its hard to Google around when you don`t know somethings name!
Since I am already wasting your guys time does any one know a function for changing numbers to this format.

Answer 1

I think this is usually called "padding" the number.

Answer 2

It's called padding.

Answer 3

Its called left zero padded numbers.