Cape Town - A woman asked her colleagues for a "Mariah Carey birthday cake," instead she got the picture of French physicist Marie Curie (who died in 1934) printed on her cake.

Writer Harriet Alida Lye explained the mix-up on Twitter, writing: "My cousin in England told her colleagues she wanted a Mariah Carey birthday cake. They misunderstood, and is the cake they made her instead. It's Marie Curie, looking very festive."

Pop icon Mariah Carey caught on to the viral tweet, wishing Harriet's cousin, Siobhan, a belated birthday.

"This could've been me if only I hadn't failed remedial math. happy birthday Siobhan!!" Mariah wrote.

Surprised at the enormous public response, Harriet tweeted on Friday: "About eight million times more people read that Mariah Carey tweet than will ever read any book I ever write,"