The Penguin Book of Curious and Interesting Numbers https://www.amazon.com/Penguin-Book-Curious-Interesting-Numbers/dp/0140261494/ref=tmm_pap_swatch_0?_encodin

The Penguin Book of Curious and Interesting Numbers https://www.amazon.com/Penguin-Book-Curious-Interesting-Numbers/dp/0140261494/ref=tmm_pap_swatch_0?_encoding=UTF8&qid=&sr= https://www.amazon.com/Penguin-Book-Curious-Interesting-Numb... The caveat here is "for some value of 'interesting'."