How do I Adapt Currency for large amounts?

I have been looking into ways of reducing the amount of space needed for currency within my game as numbers begin to get very large, very fast!

Here is what I currently have (Please excuse the graphics as they're the least of my priorities at the moment)

http://tda.pixel-virtuosa.com/game/HTML5/

I would like to try and format my currency to be more like Clicker Heroes. ( http://www.kongregate.com/games/Playsau ... lete=click )

Any help on this would be greatly appreciated. This is my first attempt at a game and this problem is really holding me back!