Although you can close out Clicker Heroes if needed and it will keep farming for you. As long as you don't delete your cache, it'll just keep adding up coins when you get to the point that you don't need to click anymore.
Yeaah :'D That's why I always try to save nightly with Cookie Clicker if I am playing that (too bad I know how to work that game that doesn't make it fun for me anymore ~w~). And Clicker Heroes. Actually, speaking of that one, I need to check on mine.