Quickly formatting a cell

Is there a way to quickly format a cell so that it acts as though it is just a number and can still be used in a formula but also have a label? For instance I would like to be able to type in "10cm" and have the cell equal 10 and have it formatted to "General \c\m".

I realize that this is possible with the cell formatting menu, and can be applied to lots of cells at once, my question is can this be done somehow by just typing into the cell so that I can enter lots of cells that may have different labels without having to go into the cell format menu for each one.

custom format as
General " c.m."

I already know how to do this in the formatting menu. I am asking if there is a way to do it while just typing in the cell.