Asked by: Joe Cairns, Edinburgh
On 26 December 2017, the largest prime number yet found – code-named M77232917 and over 23 million digits long – was uncovered by a member of a global team of computer enthusiasts. But apart from brief fame and a cheque for $3,000, there seems little point, as even the Ancient Greeks knew that there’s an infinite number of the things. The only real practical value comes from using the search algorithms to give new computer hardware a workout.
Robert is a science writer and visiting professor of science at Aston University.