# 2

This number is a prime.

Just showing those entries submitted by 'Rupinski': (Click here to show all)

The only prime which is the average of two consecutive terms of the Lucas sequence. [Rupinski]

The first 2 primes are the only 2 primes which are minimal primes in all bases. [Rupinski]

Given any even digit E and any odd digit O, integer D, and 0 ≤ R < 2^{D}, there is exactly one number D digits in length containing only the digits E and O which leaves remainder R when divided by 2^{D}. [Rupinski]

It can be shown that the probability that the greatest prime factor of a random integer n is greater than sqrt(n) is ln 2. [Rupinski]

The sum of the reciprocals of the divisors of a perfect number (including the reciprocal of the number itself) is always equal to 2. [Rupinski]