A 51-year-old FedEx employee and maths fanatic has found the world’s largest prime number after a 14-year search.
Jonathan Pace, an electrical engineer based in Germantown, Tennessee, is set to receive a £2,200 ($3,000) reward for his find.
Dubbed M77232917, the prime – a number greater than one that is only divisible by one and itself – has more than 23 million digits.
A number with more than 23 million digits has been confirmed as the largest prime number ever found. The prime – a figure greater than one that is only divisible by one and itself – has been dubbed M77232917 (stock image)
The record-breaking figure was found by Mr Pace as part of the Great Internet Mersenne Prime Search (Gimps), an international volunteer group searching for obscure primes.
It comprises 23,249,425 digits, which if printed in full with one-millimetre digits would stretch the length of more than 1,500 London buses.
The figure is nearly one million digits longer than the previous world’s longest prime, discovered in January 2016.
‘I’m very surprised it was found this quickly; we expected it to take longer,’ Professor Chris Caldwell, a mathematician who runs a website on the largest prime numbers at the University of Tennessee at Martin, told the Guardian.
‘It’s like finding dead cats on the road. You don’t expect to find two so close to one another.’
While smaller primes find uses in encryption and other applications, longer ones are more for show, with the new record-holder described as a ‘museum piece’ by Professor Caldwell.
A computer volunteered by Mr Pace reached the figure by multiplying two by itself nearly eighty million times and then subtracting one.
It took the programme six days to calculate the new record-holder, which has since been confirmed by the computers of four other Gimp volunteers.
The figure belongs to a rare group of so-called Mersenne primes, named after 17th century French monk Marin Mersenne.
The record-breaking number was found by Jonathan Pace as part of the Great Internet Mersenne Prime Search (Gimps), an international group of volunteers searching for obscure primes (stock image)
Like other primes, a Mersenne is only divisible by one and itself, but must also be calculated by repeatedly multiplying twos together and then taking away one one.
Other Mersenne primes include 7, 31, 127, and 8191.
The previous world’s longest prime number was the 49th Mersenne ever found, making the new record-holder the 50th.
Those interested in the obscure numbers can join the worldwide hunt by downloading a free computer programme online.
Gimp’s next goal is to find a Mersenne prime with more than 100 million digits – a feat worth a staggering £110,00 ($150,000) award administered by the Electronic Frontier Foundation.
Asked why mathematicians strive to find larger and larger prime numbers, Professor Caldwell said: ‘They are exciting to those of us who are interested in them. It’s like asking why do you climb a mountain.’