The physical education student — who said she will use the cash to build homes for poverty-stricken families — was the subject of 15 bids, the 'New York Daily News' reported.
Catarina's move sparked outrage across the globe as she revealed that she would be followed every step of the way by an Australian crew for a documentary film called "Virgins Wanted".
"I saw this as a business. I have the opportunity to travel, to be part of a movie and get a bonus with it.
"The auction is just business, I'm a romantic girl at heart and believe in love. But this will make a big difference to my area," she told Folha newspaper.
Catarina will be "delivered" to her buyer on board a plane between Australia and the US — being interviewed before and after loosing her virginity at a secret location.
Natsu will retain a right to be anonymous, without his picture appearing in the media, the report said.
Catarina previously said she wanted to plough the money — $20,000 and 90% of the final auction price — into a non-governmental organisation that will construct modern houses in her home state of Santa Catarina.
She signed up to the project two years ago when she saw an advertisement by Thomas Williams Productions looking for virgins to film.