YouTube trend manager Kevin Allocca said the video reached that milestone Thursday morning, MTV reported. Allocca told the Los Angeles Times it is now being watched about 20 million times every day.
The clip has also been liked by more than 6 million people, another record, Yonhap News Agency reported.
Presumably, since the world population is still a bit more than 7 billion, many of those who have watched PSY's clip have been it more than once. The Times said one Londoner has reported he has to play the clip every time his baby is fed -- or the infant will not eat.
Justin Bieber is in the No. 2 spot, with "Baby" at 815 million views.
PSY was almost unknown outside his own country when he released his sixth album this year. Alloca said the clip posted on YouTube in late July began climbing within weeks.
The Canadian Bieber also got launched on YouTube. But by the time "Baby" was in the hundreds of millions he had the backing of a major record label, something PSY did not have this summer although he does now.
"When I'm reflecting on the year, it was the biggest year ever, not only for my career, but my life and my family's life," PSY told MTV News earlier this week. "When I perform 'Gangnam Style' all around the world, I feel happy and sorry at the same time because people have no idea what I'm talking about! They're just waiting for the sexy ladies to come out! But I came to the conclusion that maybe people have their own lyrics for the song, which probably only made it more popular."
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