Pi Day was yesterday, so today mathematicians who swore allegiance to the Dark Side are celebrating something more sinister: Belphegor's Prime.
Belphegor's Prime is a prime number - you know, a number greater than 1 that cannot be wholly divided by any other number besides 1 and itself.
But it's not just any prime number. For one, it's a palindromic prime number. Then, there's the 666 hiding among the zeroes:
1000000000000066600000000000001
The symbol of Belphegor's Prime is an upside down Pi - derived from a bird glyph first seen in the mysterious Voynich Manuscript.
Saint Wolfgang and the Devil by Michael Pacher
Those of you who have read John Milton's Paradise Lost and Victor Hugo's The Toilers of the Sea would recognize Belphegor as one of the seven Princes of Hell and the demon of inventiveness (he's the prince of "Vanity and Sloth" and seduces people by suggesting ingenious inventions will make them rich).
From Cliff Pickover | If you like that, you'd love Cliff's The Math Book, which is filled with mathematical wonders and curiosities
Previously on Neatorama: The Math Book: Milestones in the History of Math