A TMZ exclusive:

Nicki Minaj doesn’t even have to sing to make bank —  sources tell TMZ Floyd Mayweather Jr. paid her $50,000  just to show her face at his daughter’s 14th birthday party.

According to  sources, Mayweather rented out the entire MGM ballroom in Vegas to celebrate  Iyanna Mayweather’s birthday last weekend — and Nicki showed  up to surprise her.

We’re told Nicki stayed for about an hour — hanging  out with Iyanna, taking pics … annnd that’s pretty much it.

Iyanna’s pretty spoiled as far as celeb guests go — last year, Justin  Bieber showed up at her party. Just imagine what her sweet 16 will look  like.”

Wow, what a lucky girl! I do wonder what her sweet sixteen will look like.