7 Cool Things Katy Perry Revealed at Her iHeartRadio Album Release Party

To celebrate the release of Katy Perry's latest album "PRISM"—and her birthday!—Katy Kats got a sweet treat on Tuesday night when they tuned in to Clear Channel's iHeartRadio Album Release Party with Katy Perry. Live streamed exclusively on Yahoo Screen from the new iHeartRadio Theater in Los Angeles, the singer radiated light and love as she sang tracks from the album, chatted with the night's MC Mario Lopez and answered fan questions in the intimate setting. Clad in a cellophane-like, white iridescent skater dress, Perry's new penchant for everything '90s was on full display – with matching hologram belt, nails and microphone, deep purple lipstick and chunky platform Mary Janes.

The event kicked off with a rousing acoustic rendition of her eighth #1 hit, "Roar," followed by a sultry version of "Dark Horse" and later took an impressive dive into "This Moment." The standouts of the night by far were the stunning ballad "Unconditionally" and the moving "By The Grace of God," both of which shone like lights through a prism in their acoustic setting.

[Related: Many Faces of ‘PRISM’: Hear Katy Perry’s Superstar Collaborations]

As promised, the night's theme was certainly "revealing," as the stripped down versions of her songs revealed the incredible power behind Perry's voice, and the Q&As revealed quite a few interesting tidbits about Katy Perry! Here are some of our favorites:

1. Her odd mementos from Taylor Swift and Miley Cyrus

Asked what she always carries in her purse, Perry revealed that she actually totes empty purses - and then revealed a surprising detail on top of that fact. Laughing, she told Lopez, "The first time I was at the Grammys, I shared a dressing room with Miley Cyrus and Taylor Swift. I asked for a lock of hair from each. I put little bows around them and put them in my empty purse and carried it around with me." If you're going to get a memento from some fellow chart-topping artists, why not go for the eBay gold? "That was really creepy, but awesome! And that's my secret. And I'm a freak," Perry joked.

2. She has worn makeup to bed for a guy

Womankind sighed with relief when Perry leveled with the audience that even she, a woman who people would die to look like, has been guilty of wearing makeup to bed! When speaking about her emotional new single "Unconditionally," she spoke of loving a person for who they really are and especially loving yourself for who you really are; something she really took to heart in the past year. With new love in her life, she's now unafraid to show her true face—and no more bedtime makeup!

3. Weirdest fan moment? Autographing someone's brain scan

You sign albums, you sign pictures and sometimes you sign right on people's skin. But Perry revealed that the strangest fan interaction was when, "One time, a girl had me sign a picture of the inside of her brain. She had something taken out. Probably her brain," she laughed. Good news, the girl was fine!

4. Perry and a lot of her tour crew have matching tattoos

In the past, the singer has gotten a tattoo to commemorate each album: a strawberry for "One of the Boys" and a peppermint for "Teenage Dream." Perry even brought a tattoo artist on tour. She said, "We open it up to the band and the dancers and the crew. Even my manager is representing with a peppermint, which they probably hate!" she joked. One of her backup singers on stage that night was repping a peppermint tattoo as well. But the tattoos were done towards the end of each tour, so a prism tattoo is on hold for now.

5. There might be a single typo in the PRISM album art

Perry said to the audience, "There's one typo in the album. If you can find it, you get a cookie." This might be a joke, but man, a cookie sounds really good right now… But if you were one of the lucky kids at the show, you could've indulged in some Katy cupcakes!

6. The "PRISM" 'ZinePak" grows flowers!

Included in the special edition of Perry's new album is a PRISM logo printed on seed paper. So if you plant that piece of paper, you'll grow a bouquet of flowers!

7. The song "Dark Horse" was inspired by the movie "The Craft"

For anyone born in the '80s, the 1996 teen witch movie "The Craft" had a whole generation of middle and high school girls ditching the pink and pigtails for black lipstick and spell books. Currently obsessed with the '90s, Perry told the audience that her song "Dark Horse" was inspired by the cult film. The song tells of spinning lyrical spells over the boy of her dreams who will surrender to the enchantment… or else!

Lightning Round!

- What is Katy's favorite song to listen to in the car? "I Wanna Dance With Somebody" by Whitney Houston

- If she could snap her fingers and travel anywhere, it would be Tokyo.

- Who would she invite to a fantasy dinner party? Freddie Mercury and Cher. Perry was ecstatic to say that Cher gave her a shoutout recently.

- The last place she took a selfie was on the set of her upcoming music video for "Unconditionally," shot in London.

- If Perry wasn't a singer right now, she would be a stylist or a stay-at-home mom.

- The most famous person in Perry's cellphone? Miley Cyrus. "She's the most famous person in the world right now."

- Every time Perry sees Mario Lopez, she sticks her finger in his irresistible dimples.

Missed Yahoo's live stream of Clear Channel's iHeartRadio Album Release Party with Katy Perry? Peek back in a few days to watch highlights from the party!

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