Just a couple of weeks ago, a new prime number was found by computers: this is 257,885,161 – 1, a number with more than 17 million digits. Wow! Known as a Mersenne prime, which is a prime number of the [… more]

Jun 09 2011

Have you heard of perfect numbers? Six is the first perfect number. It is regarded as “perfect” because it is equal to the sum of its proper divisors (or aliquot sum); these divisors include 1 but exclude the number itself. [… more]