The number you are referring to is known as “1729,” which is also called the Hardy-Ramanujan number. It is the smallest positive integer that can be expressed as the sum of two cubes in two different ways. The two pairs of cubes that add up to 1729 are:

1. 1729 = 1³ + 12³
2. 1729 = 9³ + 10³

This number gained significance when the mathematician G.H. Hardy visited his colleague Srinivasa Ramanujan in the hospital. Hardy mentioned that he traveled in a taxi with the number 1729, considering it to be a rather dull and uninteresting number. However, Ramanujan disagreed and stated that it was a very interesting number since it was the smallest number that could be expressed as the sum of two cubes in multiple ways. This incident led to the number 1729 being named the Hardy-Ramanujan number in their honor.

Hope it helps 🙂