With her new single ''California Gurls'' climbing the charts and her new album in the works, the singer is ready for another wild ride

Pop star Katy Perry was recently anointed the hottest woman alive by Maxim, and she’s flattered. She’s also pretty sure she’s being punked. ”I think it’s a practical joke they’re playing on me,” she says. ”Obviously I’m not the most beautiful woman in the world.” She looks down at her outfit. ”Um, definitely not today.”

Perry is dressed in workout pants, a lavender hoodie, a Dodgers cap, and aviator sunglasses. Perched cross-legged on a banquette in the extravagantly run-down lobby of a Hollywood rehearsal studio, she looks less like the woman who helped kick Angelina Jolie down to No. 38 and more like your cute next-door neighbor on the way to a softball game. Guess she didn’t call her breakthrough album One of the Boys for nothing. ”I’d probably be number 99 in this outfit,” the 25-year-old singer jokes, tugging on her sweatshirt. ”Maybe they took into account that beauty isn’t skin-deep.”

Hot or not, it’s hard to deny Perry’s star power. Her trunk-bumping new single ”California Gurls” rocketed to No. 1 on iTunes and into heavy rotation on radio seemingly within minutes of it leaking online (she’ll perform the tune on the MTV Movie Awards June 6), which bodes well for her upcoming album, Teenage Dream, due Aug. 24. She’s already got a platinum album under her candy-colored belt thanks to 2008’s One of the Boys, which yielded three top 10 singles, including ”I Kissed a Girl.” With her pinup-girl looks and lavish production numbers, Perry sells herself as sexy, flirty, and approachable. These days, that’s partly an act: She’s engaged to randy comedian Russell Brand, 34. ”Maybe some people will be like, ‘Oh, [now] I can never have sex with her!”’ Perry says. ”But I was never gonna really have sex with you in the first place. I want to be your fantasy. Not in a perverted way. Just in a nice teen-dreamy way.”

Perry writes or co-writes all of her songs, and ”California Gurls” — with its disco riff, top-down beat, and Snoop Dogg cameo — is the kind of infectious track only a true student of the form could craft. It’s the Santa Barbara native’s answer to Jay-Z’s ”Empire State of Mind,” and it’s already stuck in heads nationwide. ”It’s just such a catchy, well-written, well-produced song,” says Sharon Dastur, program director at New York’s Z100. ”I definitely think it’s going to be one of summer’s biggest songs.” The track’s producer and co-writer, Dr. Luke (who worked on ”I Kissed a Girl” and ”Hot N Cold,” as well as hits for Kelly Clarkson and Avril Lavigne), says Perry showed up for the Teenage Dream sessions with a CD of artists who inspired her, like ABBA and Norwegian pop chanteuse Annie. ”I think she wanted fun on this record,” he says. ”She’s a badass. She has an awesome voice, and she writes really good lyrics. She knows what she wants to say.”

Perry started writing Teenage Dream last October. ”It’s a perfect snapshot of where I am now,” she says. ”The dimensions are vast — but you have to dig. You can’t just buy a single here, a single there.” Fans who pull out a shovel will find more mature efforts that show off her voice, like sweet piano ballad ”Not Like the Movies” and a passionate devotional called ”Fireworks” that’s based on a quote Brand passed along from Jack Kerouac’s On the Road (all song titles are tentative). Perry says she used the writing process to get a few ”anvils” off her chest; songs like the blissfully romantic title track and breakup rant ”Circle the Drain” seem directed at men in her life, both past and present. ”I struggle with the idea of just being a club-banging-type girl,” Perry says, and hints that she might someday strip down her sound. ”I think my masterpiece will be pregnant, barefoot, with a guitar, making an acoustic record. That’s my soul. I also know I can make an arena full of people jump. They’re different magic tricks. I don’t need to play all my cards at once.”

And why ditch the club stuff when it’s so much fun? Take new track ”Peacock,” in which Perry chants ”Are you brave enough to let me see your peacock?” over a ”Hey Mickey”-ish beat. ”I’m hoping it will be a gay-pride anthem,” Perry says. ”Peacocks represent a lot of individuality…. It’s not just like, ‘I wanna see your bulge.”’ When it’s pointed out that she’s not exactly chanting ”pea-bulge,” Perry actually seems offended. ”It does have the word c–k in it, but art is also in fart! It’s all in how you look at it.”

Like any good modern media mogul, Perry is also busy evolving as a personality. She served as a guest judge on the current season of American Idol, getting into a verbal slap fight with Kara DioGuardi (”That was all editing,” she says, ”but I think it was genius”), and she’s the voice of Smurfette in the upcoming Smurfs movie. Perry says the film’s producers picked her out of an anonymous pile of recordings for the role — she can turn on quite the squeak when necessary — and that she’d love to do more animation, maybe play ”a chair in a Pixar movie or something.” In live-action news, she recently made a trip to Sesame Street to sing ”Hot N Cold” with Elmo, and wouldn’t mind a casting call from Judd Apatow. ”If they make Superbad 2, put me in a fat suit and I’ll do it.”

Meanwhile, she’s getting more than enough laughs at home, thanks to her eight-month relationship with Brand. ”Listen, there is never a dull moment in my life anymore,” Perry says. ”It’s like a comedy show, 24/7.” Any relationship between celebrity types is likely to be pecked to death, but Perry finds comfort in their shared spotlight, too. ”We were driving home the other day,” she says. ”I had picked him up from a shoot, and he had the same amount of buzzing people around him that I do. I never thought my partner was going to be the same diva in demand as me.”

Although she says ”diva in demand” with tongue in cheek, it’s not much of a brag. Neither as pure as Taylor Swift nor as kooky as Lady Gaga, Perry has found her place as a uniquely accessible megastar, the Hottest Woman Alive who’s also just one of the gurls. ”I’m not hipster cool, and I’m not popster lame,” she says. ”I want to have fun and go out with my friends. I don’t want to be unattainable.” Pause. ”I’m still not going to have sex with you, though.”