The place where Wilt Chamberlain famously banged a large portion of his alleged 20,000 hookups is for sale ... and can be yours for a small fee of $18.99 MILLION!!

You know the story ... the NBA legend claimed the number of women he slept with was in the tens of thousands -- and the mansion that harbored his "sex room" and presumably the majority of those trysts has now hit the market.

Sadly ... most of the features that made it Wilt's -- mink-lined waterbed floors, mirror-covered walls and a golden bathtub -- have been remodeled.

But the place is still dope ... featuring six bedrooms, six bathrooms, 7,158 square feet ... and gated parking for 20-plus cars!!