Shawn Mendes’ Vine success cultivates No. 1 hit ‘Stitches’

Shawn Mendes has achieved a lot in the past two years since he made the leap from teenage Vine sensation to pop star.

His debut album, “Handwritten” (Island), hit No. 1. He was the opening act for Taylor Swift’s stadium tour last summer and his upcoming world tour, which kicks off at Radio City Music Hall on March 5, essentially sold out completely within minutes. But the strangest first of Mendes’ young career may also be the most telling.

Last month, his single “Stitches” hit No. 1 on Billboard’s adult pop charts. That’s right, Mendes has topped the adult pop charts even before he graduates from high school, before he becomes a legal adult.

And he knows that’s a big deal.

“It’s phenomenal for me,” says Mendes, calling from his home in Pickering, Ontario. “I think the biggest fear of a 17-year-old artist — my voice doesn’t exactly sound mature yet — is not being accepted in the adult world. When ‘Stitches’ started to react to more than kids and teenagers, that kind of says to you, ‘Hey, man, you’ve got a good shot at a long career.’ . . . It is weird, but it’s more incredible and satisfying because that’s what you want. You want your songs to reach people from 5 years old to 60 years old and have people like it.”

Oddly enough, when people like Mendes’ music, it’s overwhelmingly because they like Mendes, and vice versa. There are no dancers in the Mendes live show. No band, though he says that will change on this tour.

Mendes was a sight to behold when he opened for Swift last summer, standing alone on the stage with his acoustic guitar, ready to entertain 60,000 or so.

“It was very nerve-wracking to me,” he says. “But as the tour went on, it became my secret weapon. No one was expecting that. It creates a different environment that not a lot of people have ever felt or seen before. . . . It was like, ‘Hey, watch me. It’s different.’ ”

Ido Zmishlany, the Valley Stream native who co-wrote and produced Mendes’ debut single, “Life of the Party,” and several other tracks including the current single “I Know What You Did Last Summer,” says Mendes is a rarity.

“There’s a number of kids on Vine or YouTube that are musical personalities and all that,” Zmishlany says. “Shawn is able to transcend that. He actually has the goods. He can sing with the best of them. And he can write.”

Zmishlany laughs about how quickly Mendes’ “I Know What You Did Last Summer” came together, the single that was dreamed up by Mendes and Fifth Harmony’s Camila Cabello backstage at Taylor Swift’s MetLife concert last year. “It was a magical session,” he says.

Mendes says the entire experience was unplanned. “Camila and I were friends from before and she was there to see Taylor,” he recalls. “We were just jamming on guitar and things started to click. The next day we were in the studio for 11 hours. It was a great ebb and flow.”

Of course, when two talked-about stars get together for a buzzed-about duet, the rumor mill shifts into overdrive — something Mendes says he tries to ignore.

“You can’t just be doing a spectacular song,” he says, adding that the pair are simply good friends. “It ends up being more.”

The rumors are simply part of the different road teenage stars have to navigate that other stars don’t.

Island Records president David Massey says that priorities for Mendes have to be different from priorities for adult artists.

“One thing that’s really important to me and obviously to his parents is to make sure that he finishes his education, so the next six months of Shawn’s career would also encompass him having to graduate high school,” Massey recently told Billboard. “It’s not quite the same as dealing with a 25-year-old.”

However, Mendes’ goals are the same as any artist. He is already at work on his second album, which he hopes will be released by the end of the summer, adding that fans may hear some new songs on the current tour.

“I just want to get together as many good songs as possible,” he says, adding that he is still processing how much his life has changed. “I’m learning more every day. That’s also why I want to create a show that feels very different.”

Mendes says he is excited about this world tour because it is bigger than he could ever have imagined.

“You don’t really know about how many people like your music until you put tickets to your shows on sale,” he says. “That we were able to sell out places, like two dates in England in a 4,000-seat venue? That’s the best feeling in the world. . . . That means a lot to me.”

And he plans on not disappointing anyone, starting with the Radio City show.

“It’s been a long time since we did a show in New York,” Mendes says, adding that he wanted to launch the tour at Radio City. “I wanted to make a statement about this tour. . . . We’re starting off with a boom.”