Get ready for some even tougher answers on those math tests. Mathematicians—with the aid of a giant network of computers—said on Tuesday that they had discovered the largest prime number—and it’s 17,425,170 digits long. Discovered by University of Central Missouri mathematician Curtis Cooper, the number—2 raised to the 57,885,161 power minus 1—crushes the last prime number discovered, which had only 12,978,189 digits. “It’s analogous to climbing Mount Everest,” said retired computer scientist George Woltman. The number is also the 48th of a rare group of primes known as the Mersenne Primes, which take the form of 2 raised to the power of a prime number minus 1—first described by French monk Mersenne 350 years ago.