Taylor Swift, Rihanna to Perform at Second Annual iHeartRadio Music Festival

Taylor Swift

Ryan Seacrest will host the two-day event at the MGM Grand in Las Vegas.

Clear Channel Media's second annual iHeartRadio Music Festival -- featuring some of the biggest names in pop, rap, rock, country, R&B and dance music -- is set for Sept. 21 and 22 at the MGM Grand in Las Vegas,

Rihanna, Taylor Swift, Lil Wayne, Aerosmith, Usher and Deadmau5 are among the 20 diverse acts lined up for the event hosted by Ryan Seacrest.

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 “The iHeartRadio Music Festival is a unique celebration of music -- it’s the biggest names in the industry coming together for an impressive weekend of live entertainment,” Seacrest said. “The momentum, energy and music experience around the inaugural iHeartRadio Music Festival was incredible, and I’m excited to be a part of this must-see event.”

This two-day event will celebrate the success of the new iHeartRadio, which launched in September and reached 10 million registered users in eight months -- faster than other such digital platforms as Facebook, Twitter, Pandora, Spotify and Instagram The online service offers access to more than 1,000 broadcast and digital-only radio stations from 150 cities, plus user-created Custom Stations inspired by favorite artists and songs.

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The other performers announced Monday are Pink, Linkin Park, Brad Paisley, Pitbull, Green Day, Swedish House Mafia, Miranda Lambert, Enrique Iglesias, No Doubt, Jason Aldean, Bon Jovi, Mary J. Blige, Calvin Harris and Shakira. Additional artists will be announced in the coming weeks. 

The first iHeartRadio fest brought to the Las Vegas Strip such top acts as Lady Gaga, The Black Eyed Peas, Jay-Z, Kelly Clarkson, Coldplay, Nicki Minaj, Jennifer Lopez, Bruno Mars, Kenny Chesney, Alicia Keys and Sting.

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“The bar was set high this year given the overwhelming success of last year’s inaugural event," Clear Channel chairman and CEO John Hogan, "and we are extremely pleased to have the opportunity to again deliver a diverse, extraordinary lineup of incredible talent to our listeners for year two of the iHeartRadio Music Festival.”

Tickets for this year's event go on sale at 1 p.m. ET July 14 via Ticketmaster.