Nikki Bella has to pay her ex-husband a whole lotta cash ... including thousands of dollars a month in child support as part of their final divorce settlement.
The former WWE wrestler and her pro dancer ex reached an agreement for Nikki to pay Artem $3,500 each month for the care of their son Matteo. She's also forking over a six-figure lump sum to him -- $100K now, and another $100K before the end of this year.