The origins of this fascinating number trace back to 1683 when the Swiss mathematician Jacob Bernoulli stumbled upon it. While Bernoulli wasn’t specifically searching for a new mathematical constant, he inadvertently discovered the first approximation of e during his studies on continuous compound interest. This makes the story of e particularly intriguing; it wasn’t the product of abstract mathematical thought, but rather a result of tangible financial studies.

In 2000, the Clay Mathematics Institute listed seven big math problems and offered a million dollars for each solution. These are called the Millennium Prize Problems. 23 years have passed, and we’re checking in to see how far we’ve come.