LONDON — The publisher of Prince Harry’s “Spare,” Penguin Random House, says 1.4 million copies of the tell-all book sold in English on its first day in bookstores in Britain and North America, as did thousands more in 14 translations around the world.

One might not have guessed the success, though, from the trickle of people seen buying the book in two of London’s leading bookstore chains, Waterstones and WHSmith. A manager at one of the Waterstone outlets told me two or three people bought it shortly after the store opened, but sales were sporadic.

There was nothing, he said, to compare this with the rush to buy the seven Harry Potter books by J.K. Rowling. Since the first Harry Potter book appeared in 1997, worldwide sales have reached 500 million.

If “Spare” isn’t quite in that league, it’s still an engaging read with plenty of inside stuff — some lurid, some critical, and much of it never previously known — about what goes on inside the royal family and all that went wrong in the relationship between Harry’s father, King Charles III, his older brother, Prince William, and his American wife, Meghan.

Don’t think, though, that Harry suddenly burst into bloom as a charming writer, a perspicacious autobiographer with an ear and eye for drama and dialogue. For that you can credit the real unsung hero, author J.R. Moehringer, an experienced chronicler of other people’s lives.

“Spare” spares little space for crediting Mr. Moehringer, a Pulitzer Prize-winning former journalist, as the co-author, though readers won’t care about the fine points of who did what for the book. The narrative maintains a breezy, easy style through the ups and downs of Harry’s life: his suffering; his love for poor, put-upon Meghan, the target of the nasty British newspapers; their escape to America; and the joys of their lives as parents.

The book is written in short paragraphs, with disclosures on just about every page, many of which were picked up in advance by the press. That might be why “the expected crowds of shoppers eager to buy Prince Harry’s book Spare failed to materialize at stores everywhere,” as the Daily Mail reported. “Just one royal superfan arrived at the flagship Waterstone store in Piccadilly, central London, for its 8 am opening while a handful turned up at WH Smith in nearby Victoria, which welcomed customers at midnight.”

That’s even though the book is priced at 14 pounds, which is about $17 dollars,  for the first week or two of sales, after which it will cost twice that amount. Not to worry, it’s still making a tidy sum for Prince Harry.