The Shake It Off hitmaker, 25, is the highest-placed woman on the 2015 list, which ranks the "extraordinary" people who are "transforming business, government, philanthropy, and so much more".

The singer comes in sixth behind Apple CEO Tim Cook at number one, European Central Bank chief Mario Draghi at two and Xi Jinping, the Chinese President.

In a related article, editors heap praise on Swift, who is ranked two spots behind Pope Francis, writing, "Pop's savviest star has crossed swords with Spotify, embraced corporate sponsorship, and moved to secure dozens of trademarks... plus she has proved shrewder at honing a brand in the social media age than virtually any other person or company. And she's done it without resorting to dumbed-down salacious gimmickry...

"With (her latest album) 1989, the top-selling album in 2014, Swift's efforts to ensure she gets paid for her music could have a huge ripple effect on the way artists are compensated in an era of free streaming."

Swift took a stand against popular music programme Spotify in November (14), removing all her tracks from the site without prior notice, just days after the release of 1989. She justified her decision by arguing that the bosses of the streaming site, which allows users to listen to millions of songs for free, aren't compensating artists and songwriters properly.

Other notable mentions on the Fortune poll include Facebook founder Mark Zuckerberg at 25, basketball superstar LeBron James at 31, and comedian and The Tonight Show host Jimmy Fallon at 45.