Black Sabbath's foundational heavy metal hit "Paranoid" has been played more than 1 billion times on Spotify.
The streaming service has an official "Billions Club" playlist which also includes tracks like "Good Days" by SZA, "I Wanna Be Yours" by the Arctic Monkeys, and "Every Breath You Take" by the Police.
"Paranoid," the title track for Black Sabbath's sophomore studio effort, peaked at No. 4 on the singles chart in the U.K. and No. 61 on the Billboard Hot 100.
Despite the widespread acclaim it's received, the track was nothing more than an "afterthought" thrown together during a recording session at Island Studios in London, bassist Geezer Butler told Guitar World in 2004.
"We basically needed a three-minute filler for the album, and Tony (Iommi) came up with the riff," he said. "I quickly did the lyrics, and Ozzy (Osbourne) was reading them as he was singing."
Black Sabbath went on to sell more than 75 million records over the course of its career, including 15 million in the U.S. alone, Billboard reported. The group has also received at least 24 platinum albums in its native U.K.
Black Sabbath was inducted into the Rock and Roll Hall of Fame in 2006.
The band's original lineup has matured a lot since "Paranoid" was released 54 years ago.
Ozzy has retired from touring and moved back to the band's native Birmingham, but the vocalist has plans for two more farewell shows in his hometown.
"He feels like ‘I have never said goodbye to my fans and I want to say goodbye properly,'" his wife and manager Sharon Osbourne said earlier this year, according to the Mirror.
"We will do it in Aston Villa where Ozzy is from," Sharon added, a reference to the Birmingham soccer team's stadium. "His voice is still absolutely perfect. And all the time he has been off he still does his singing lessons so his voice is perfect. And he can joke yeah."
The singer is now 75 and struggling with health issues, but Sharon didn't try to temper expectations.
"He has all these melodies in his head," she said. "Even if you don’t like his music you can’t not like Ozzy, he just draws you in."
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Late last year, guitarist Tony Iommi collaborated with System of a Down frontman Serj Tankian and Gibson CEO Cesar Gueikian on a track called "Deconstruction."
Gibson also auctioned off a painting made by Tankian and a one-of-a-kind Les Paul Standard adorned with the artwork.
Proceeds from the sale were donated to the Armenia Fund, which provides humanitarian assistance like health care and disaster relief programs to people in the country and other Armenian communities worldwide.
Gueikian and Tankian are both of Armenian descent.
"It was great to hook up with Serj again and also to do a track with Cesar (I think that he’s trying to steal my job!! ) ha-ha!!" Iommi said. "The Armenian people are really lovely people, and it’s a great pleasure, a great cause, and I’m very happy to be involved in it."
