Tyga -- Drops $2.2 Mil On Topless Model

Tyga just bought a sweet ride as a birthday present to himself ... it's got four doors and four wheels -- hey, just like a Toyota Camry -- but Tyga's whip cost around $2.2 million.

Sources close to Tyga tell us he dropped 2 large bills plus on a 2014 convertible Maybach 62 S Landaulet -- the car itself cost $1.3 mil. Now get this ... he spent nearly a mil tricking it out.

West Coast Customs hooked it up with all kinds of extras, including a 40 inch TV. Check out the pics.

Here's the thing ... for $2.2 mil where the hell are the cup holders?

Ty joins an elite group of 62 S owners -- including Jay Z and Bird Man. We're told he plans to showcase the car in a new video he's shooting with Mally Mall, "Wake Up In It."