Right now, 2.668.638 in White 2. I've spent a lot on Super Repels for Funfest missions, however. (Why Super? When you buy 180 Repels the ratio prize/steps does matter. Super Repels are slighty cheaper than Max Repels)
About 1.5 mil in Black 2. This game is far too easy in that department, got a boat load of items that cover my needs, and far too much money. SS is pretty decent in that department, and it lets you struggle a little bit if you're not careful.