Converting number to have leading zeros and punctuation mark

Trying to assist a colleague with this. He said that the person that trained him on his spreadsheet showed him a way to make it come out the way we want, but he did not take notes. The other person retired over a year ago so we don't know what she had done. Essentially we are attempting to get the same result as when you physically type '0003 into the cell (which gives you 0003 with the little warning message that a number is stored as text) from an initial value of 3. Seems odd, but the apostrophe has to be there due to how the data pulls from the sheet to where it gets downloaded. And we are trying to find an easier way than manually updating 500 cells.