A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. This simple definition holds the key to our identification method.

These rare numbers, discovered by Euclid in 350 B.C., can be written using the formula 2^p – 1, where p is also a prime number. (In this case p equals 20,996,011.) Most prime numbers cannot be written ...

Twin primes are two prime numbers that have a distance of two on the number line; that is, they are directly consecutive if you ignore even numbers. Examples include 3 and 5, 5 and 7, and 17 and 19.

Prime numbers, such as 2, 3, 5, 7, 11, and so on, are divisible only by 1 and themselves.