ARI SHAPIRO, HOST:
I don't want to ruin your day, Juana. But are you ready for a math pop quiz?
JUANA SUMMERS, HOST:
No.
SHAPIRO: What do the numbers two, three, five, seven, 11 and 13 have in common?
SUMMERS: OK, luckily, I know this one. They are all prime. And if you keep going higher - like, way, way, way higher - you'll get to the largest prime number known to humankind.
LUKE DURANT: It's a number with something like 41 million digits, just slightly over. I've grown up thinking a billion was sort of an unfathomable number, and that has 10 digits.
SHAPIRO: That's Luke Durant, the researcher and amateur mathematician who identified this new prime number last month. The number is two to the power of 136,279,841. And after calculating that, you subtract one. The resulting number is so large...
DURANT: It can be read out loud, but it would take, I believe, several years. I think I saw if this were in a book, it would be 15,000-20,000 A-4 pages.
SUMMERS: To get started, Durant worked with the Great Internet Mersenne Prime Search community, a volunteer collaboration begun in 1996.
SHAPIRO: We'll note that Mersenne primes are a special kind of prime number named after a French monk who studied them roughly 400 years ago. And this newly discovered number is a Mersenne prime.
SUMMERS: These record-breaking prime numbers are so large, they take an incredible amount of computing power to find. Years can go by between discoveries. The last was found way back in 2018.
DURANT: It's kind of a sifting of grains of sand through some filter and eventually sift it long enough and try to find the small pebble that doesn't make it through the grates.
SHAPIRO: Now, Durant is not a mathematician by trade, but he had an idea for how to speed up that sifting process 'cause he used to work for the chip company in NVIDIA, developing GPUs, or graphics processing units, which are a vital part of AI infrastructure.
DURANT: I decided to bring my expertise and interest and see how large of a computer I could put together using GPUs and the new software and see if that can accelerate time to the newest, largest prime number.
SUMMERS: Durant built a really large computer made up of thousands of servers spread across 17 countries. Even then, he couldn't be sure he would succeed.
DURANT: As much as I was putting into the project, it was extremely unlikely that I came out with a result.
SUMMERS: But just about a year after he started, he struck prime number gold.
DURANT: I wanted to show that, given the strength and capability of large systems that are generally available, even a single individual can start pulling those systems together to come out with surprising new results.
SHAPIRO: There are some uses for prime numbers in fields like cryptography and communication. But Luke Durant says he's not aware of any practical application for this new number.
SUMMERS: Even so, his discovery is making a practical impact. Durant won $3,000 for finding the new prime, which he says he's donating to the math department of his alma mater, the Alabama School of Math and Science.
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