In addition to owing his fans apologies for beating and slapping them, the IRS says Katt Williams owes the government $4 million in unpaid taxes.

Which begs the question: Jesus, how much does this dude make?

The comedian was hit with the lien based on $3.2 million owed in 2008 and $830,000 in 2009. And it isn't the first time that Uncle Sam has come a-calling -- in 2010, Williams was dinged with a $284,000 tax tab.

For a guy rolling around in that much coin, you'd think he'd use some of it to hire a few competent accountants to keep him out of trouble.

The huge bill is just the icing on the troubled cake Katt has been eating this year, topped off with multiple arrests and lawsuit sprinkles.

Maybe he'll clean up his act in 2013. Or maybe not -- being such a mess is clearly pretty damned profitable.