Books like Letters to a Young Mathematician
Ian Stewart
Letters to a Young Mathematician is 224 pages, about 4 hours 6 minutes at 250 words a minute.
7 books to read next
How long each takes
How Not to Be Wrong 8.6 h 
The Simpsons and Their Mathematical Secrets 4.8 h 
Humble Pi 6.2 h 
What If? 5.8 h 
Mathenauts 5.5 h 
The Planiverse 4.9 h 
Love and Math 6.1 h Bar height shows length. Estimated at 250 words a minute.