Katy Perry during the 28th Annual ARIA Awards 2014 at the Star on Nov. 26, 2014, in Sydney, Australia.

Katy Perry performs live at the Brisbane Entertainment Centre on Nov. 27, 2014, in Brisbane, Australia.

Singer Katy Perry attends the Costume Institute Gala for the "Punk: Chaos to Couture" exhibition at the Metropolitan Museum of Art on May 6, 2013, in New York.

Katy Perry attends "The Smurfs 2" party at The 5th Annual Summer Of Sony at the Ritz Carlton Hotel on April 22, 2013, in Cancun, Mexico.

Katy Perry arrives at the 55th Annual Grammy Awards at Staples Center on Feb. 10, 2013, in Los Angeles.

John Mayer and Katy Perry attend the presidential inauguration on the West Front of the U.S. Capitol on Jan. 21, 2013, in Washington.

Singer Katy Perry arrives on the red carpet at a central London cinema for the European premiere of her film, "Katy Perry: Part of Me" on July 3, 2012.

Singer Katy Perry arrives at the 54th Annual Grammy Awards held at Staples Center on Feb. 12, 2012, in Los Angeles.

Singer Katy Perry and actor Russell Brand attend the 3rd Annual "Change Begins Within" Benefit Celebration presented by The David Lynch Foundation held at LACMA on Dec. 3, 2011, in Los Angeles. Married in 2010, the couple filed for divorce on December 30, 2011.

Singer Katy Perry makes an appearance at Nordstrom at The Grove at Farmers Market to launch her new fragrance, "Meow!," on Dec. 14, 2011, in Los Angeles.

Singer Katy Perry, winner of the Video of the Year Award for "Firework," Best Collaboration Award (featuring Kanye West) for "E.T.," and Best Special Effects in a Video for "E.T.," poses in the press room during the 2011 MTV Video Music Awards at Nokia Theatre L.A. LIVE on August 28, 2011, in Los Angeles, California.

Katy Perry attends the premiere of "The Smurfs" at the Ziegfeld Theater on July 24, 2011, in New York.

Singer Katy Perry arrives for the 53rd annual Grammy Awards at the Staples Center in Los Angeles on Feb. 13, 2011.

Katy Perry arrives at the MTV Video Music Awards in Los Angeles, Sept. 12, 2010.

Singer Katy Perry poses in the press room at the 2010 MTV Movie Awards at the Gibson Amphitheatre in Universal City, Calif., on June 6, 2010.

Actor Russell Brand and singer Katy Perry pose on the red carpet as they arrive for the premiere of his movie, "Get Him to the Greek," at the Greek Theatre in Los Angeles on May 25, 2010.

Married in 2010, the couple announced in December 2011 that they were seeking a divorce.

Singer Katy Perry arrives at the 14th Annual Critics' Choice Awards on Jan. 8, 2009 in Santa Monica, Calif.

Singer Katy Perry performs at the 2008 MTV Video Music Awards held at Paramount Pictures Studio Lot on Sunday, Sept. 7, 2008, in Los Angeles. The California singer, born in 1984, gained fame in 2008 with her provocative single, "I Kissed a Girl."