Michelle Obama's memoir "Becoming" could become the biggest-selling autobiography ever, its German publisher said, expressing optimism that husband Barack's forthcoming account of his two terms as president will also be a hit.

The former first lady's recollections, for which she received a reported advance of more than $60 million from Bertelsmann's Penguin Random House division, has sold 10 million copies since it came out in November.

"That makes it our most notable creative success of last year," Bertelsmann CEO Thomas Rabe told a news conference, reporting a 2.8 percent gain in annual revenue at the 183-year-old publisher.

Barack Obama has also signed with Penguin Random House to publish his White House memoir. Bertelsmann hopes it will be published this year although no firm date has yet been set.

Still, Penguin Random House — one of Bertelsmann's eight divisions — reported only a 1.3 percent rise in revenue last year as bestsellers and increased audio book sales helped to offset a broader drift away from print by readers.

Bertelsmann's interests also span television, music and magazine publishing, exposing it to disruption from Silicon Valley tech giants including Apple, which unveiled new subscription TV and news aggregation services on Monday.

Rabe, calling Apple TV+ "just another streaming platform," said Bertelsmann's TV arm RTL Group would stick to its plan to ramp up video-on-demand services, betting on local content to attract viewers in its European markets.

Asked whether Bertelsmann would make available its magazine titles via Apple News+, a $10 a month subscription service, Rabe said: "If this kiosk achieves scale, and the conditions are right, I don't see why we shouldn't take a look."