Ad revenue from popular YouTube videos is shared with creators of the content.
In December, "Gangnam Style" became the first video to break a billion views on YouTube, marking a historic milestone on the Internet.
A counter at the YouTube page showed that the music video has been watched more than 1.23 billion times since it was uploaded in July of last year.
Kevin Allocca, YouTube's trends manager, attributed Psy's success "to the universal appeal of catchy music -- and er, great equine dance moves."
"Gangnam" is estimated to have earned the rapper millions more from digital downloads, advertising deals and on-demand services.
The song -- which refers to a trendy Seoul district -- spawned a mini tribute video industry, complete with copycats.The quirky star, whose real name is Park Jae-Sang, won adulation in his homeland for the global hit and was awarded one of South Korea's highest cultural honors, the Okgwan Order of Cultural Merit.