A basic feature of number theory, prime numbers are also a fundamental building block of computer science, from hashtables to cryptography.

The number certainly doesn't seem particularly exciting. It's not a prime number or a power of 2 or the square of some other number. The digits don't seem to follow any obvious pattern.

Both arithmetic aficionados and the mathematically challenged will be equally captivated by new research that upends hundreds of years of popular belief about prime numbers.

An effort in which thousands of people donate their computers' unused processing power uncovers the largest prime number so far known.

Despite finding no specific examples, researchers have proved the existence of a pervasive kind of prime number so delicate that changing any of its infinite digits renders it composite.

The Riemann hypothesis is the most important open question in number theory—if not all of mathematics. It has occupied experts for more than 160 years. And the problem appeared both in ...

The twin primes conjecture is one of the most important and difficult questions in mathematics. Two mathematicians have solved a parallel version of the problem for small number systems.

A prime number is a whole number that can only be divided by 1 and itself. A former Nvidia programmer discovered the world's largest known prime number using graphics processing units.

An effort in which thousands of people donate their computers' unused processing power uncovers the largest prime number so far known.