Mathematicians discover 46th prime number.

LOS ANGELES, Sept. 27 (UPI) -- Mathematicians at UCLA say they have discovered a 13-million-digit prime number long sought by computer users.

Finding the first verified Mersenne prime number with more than 10 million digits qualifies UCLA for a $100,000 prize from the Electronic Frontier Foundation, an activist group supporting individual rights on the Web, the Los Angeles Times reported Saturday, noting the discovery is the 46th known Mersenne prime number.

"We're delighted," said UCLA project team leader Edson Smith. "Now we're looking for the next one."

Prime numbers are divisible only by themselves and one, such as the numbers three, seven and 11. Mersenne primes, named after the 17th century French mathematician Marin Mersenne, take the form 2P -1, where P is also a prime number, the Times reported, adding the new UCLA prime is P = 43,112,609.