Luke Durant, a researcher and amateur mathematician, has identified the largest new prime number known to humankind. The newly discovered prime number is 2 to the power of 136,279,841, then minus one.

There's a new behemoth in the ongoing search for ever-larger prime numbers — and it's nearly 25 million digits long. A prime is a number that can be divided only by two whole numbers: itself and 1.

Prime numbers—integers that are divisible only by themselves and 1—are the easiest path into understanding both rigor and mysticism in mathematics. Euclid’s proof that there is an infinite number of ...