The online computer game “Is this prime?” tests a player’s knowledge of prime numbers—and just surpassed 2,999,999 attempts. Give it a whirl.

Somewhere out there on the number line, huge prime numbers are lurking, waiting to be discovered. On Wednesday, a new one was. The Great Internet Mersenne Prime… ...

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 ...

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.

The largest known prime number has been discovered, smashing the previous record by more than 16 million digits.

Say hello to the world's largest prime number. Prime numbers, which are divisible only by one and themselves—such as one, two, three, five, seven, 11 and so on—become less common as numbers ...

The new number has 17,425,170 digits —just writing them down makes for a 22.45-megabyte text file. The UCLA number had knocked an earlier number of Cooper’s, from 2006, out of the record books.