55558...50621 (680-digits)

This number is a prime.

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

As of May 2001, the primitive part p of the Fibonacci number F₄₈₈₁ = 2*F₁₆₂₇*p is the largest prime for which all the factors of p² - 1 have been discovered. [Broadhurst]