Researchers find largest prime number yet

KANSAS CITY, Mo. — Mathematicians at the University of Central Missouri have identified the largest prime number yet, but good luck remembering it.

The university said Wednesday that a group led by computer science and mathematics professor Curtis Cooper found the 17 million-digit prime number last month. It is the 48th known Mersenne prime and is the third discovered at the 11,800-student university in Warrensburg, about 50 miles east of Kansas City.

Primes are numbers such as 3, 7 and 11 that are divisible only by themselves and 1 without leaving a remainder.

Mersenne primes are named after the 17th century French mathematician who discovered them, Marin Mersenne. They’re expressed as 2P-1, or two to the power of “P” minus one. P is itself a prime number. For the new prime, P is 57,885,161.

The number was independently verified using different programs running on different hardware, according to the Great Internet Mersenne Prime Search, or GIMPS, a cooperative in which underused computing power is harnessed to perform the calculations needed to find and verify Mersenne primes.

The university, which is affiliated with the worldwide computing project, used about 1,000 campus computers in its search. Special software allows students to check email and write papers on campus computers while the machines’ excess computing capacity searches for the elusive numbers.

The school also found then-record prime numbers in 2005 and 2006. Mathematicians at UCLA broke the Missouri school’s record in 2008 with a 13 million-digit prime number.

Cooper, whose group’s latest finding is eligible for a $3,000 research award, said each subsequent prime number is tougher to find.

“Every time I find one it is incredible,” Cooper said. “I kind of consider it like climbing Mount Everest or finding a really rare diamond or landing somebody on the moon. It’s an accomplishment. It’s a scientific feat.”

Mike Breen, a spokesman for the American Mathematical Society, said the large prime numbers are exciting for mathematicians and computer scientists. He noted the latest number discovered is so enormous that is would take reams and reams of paper to print it out.

“It is great to test computers,” Breen said. “When they find a number, they have to find out, it looks like it might be a prime, but they don’t know for sure, so they have to do all kinds of tests on it. That is a good way to test how your algorithm is working, how fast your computer is. Things like that.”

Meanwhile, the hunt continues for a 100 million-digit prime number, which could fetch a $150,000 prize from the Electronic Frontier Foundation, a San Francisco-based nonprofit.

More in Local News

Video shows man suspected of attacking a woman in Edmonds

The man allegedly threw her on the ground, then ran away after the she began kicking and screaming.

Former Monroe cop loses appeal on sex crimes conviction

Once a highly respected officer, he was found guilty of secretly videotaping his kids’ babysitter.

Suspect sought in two Everett bank robberies

He’s described as 5-foot-10 to 6-foot-1, with dark hair and a goatee, and may have a neck tattoo.

Navy to put filter in Coupeville’s contaminated water system

Chemicals from firefighting foam was found in the town’s drinking water.

Two missing men found, one alive and one dead

The man found alive was found in an apartment across the hallway and taken to a hospital.

Darrington School Board dealing with upheavals

The crux of the controversy seems to be the superintendent’s job.

Alaska Airlines has selected destinations for new service from Paine Field. (Alaska Airlines)
Alaska Airlines will fly from Everett to 8 West Coast cities

Two destinations that didn’t make the list were Spokane and Hawaii.

Train kills man who was trying to get off tracks in Monroe

The conductor said he attempted to stop after sighting the man, who’d been lying on the rails.

Roommate suspected in Edmonds killing found hiding in closet

Police had been searching for him for 10 days before locating him at a house in Everett.

Most Read