Your first choice is in Portuguese.
A fascinating property of maths is that it is totally international and never goes out of date. So if you write a maths classic it is a classic for ever, everywhere. This Brazilian book links my past life in Brazil with maths. The literal translation of the Portuguese title is ‘The Man Who Calculated’ but the English version is called The Man Who Counted. There are editions in many other languages too.
The author Malba Tahan is a fictional character, the pen name of Júlio César de Mello e Sousa, and the book is set in Arabia as a mixture of One Thousand and One Nights and a maths book – it’s coming out of the most populous Catholic country in the world and yet it’s as much a love story to Arab culture as to maths itself. There were lots of Arab immigrants in Brazil and they love Arab culture – one of the most popular fast food chains is called Habib’s. The story here is presented as if the author, who I believe only went to Lisbon once and virtually never left Brazil, has just stumbled upon or discovered this Arab text.