Researchers in September 1996 found the largest one of these ever. It would take 12 pages of newspaper to print it. What was it?

A prime number is a whole number greater than one that cannot be formed by multiplying two smaller whole numbers; its only positive divisors are one and itself. For centuries, mathematicians have been fascinated by these fundamental building blocks of arithmetic, and the search for ever-larger primes has been an ongoing quest. In September 1996, researchers made a significant discovery, uncovering a prime number so immense that simply printing it out would require a staggering 12 pages of newspaper.

This colossal number was a Mersenne prime, a special type of prime expressed in the form 2^p - 1. Specifically, it was the 34th known Mersenne prime, 2^1257787 - 1, discovered by mathematicians David Slowinski and Paul Gage on September 3, 1996. Its discovery was notable as it was the last record-breaking prime found without the aid of the Great (Review) Internet Mersenne Prime Search (GIMPS), a distributed computing project that has since harnessed the power of thousands of volunteer computers worldwide to continue the hunt for these elusive giants.

The pursuit of these enormous primes, often hundreds of thousands or even millions of digits long, is driven by both mathematical curiosity and the practical application of testing computer hardware and algorithms. While not directly used in modern cryptography, which relies on different types of large numbers, the search for Mersenne primes pushes the boundaries of computational power and helps us better understand the distribution and properties of numbers. It’s a testament to human ingenuity and collaborative effort, transforming the abstract world of mathematics into a real-world pursuit.