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jesternl · Yankee Doodle Dutchie

Just had to post this one:

666 = 2 ² + 3 ² + 5 ² + 7 ² + 11 ² + 13 ² + 17 ²

= 1 + 2 + 3 + 4 + 567 + 89

= 123 + 456 + 78 + 9

= 9 + 87 + 6 + 543 + 21

= 1 ³ + 2 ³ + 3 ³ + 4 ³ + 5 ³ + 6 ³ + 5 ³ + 4 ³ + 3 ³ + 2 ³ + 1 ³

Found on http://www.futilitycloset.com/

and some more:

The Dewey Decimal System classification number for "Numerology" is 133.335. If you reverse this and add, you get

133.335 + 533.331 = 666.666
Also
666 ⁴⁷ = 5049969684420796753173148798405564772941516295265
4081881176326689365404466160330686530288898927188
59670297563286219594665904733945856

666 ⁵¹ = 9935407575913859403342635113412959807238586374694
3100899712069131346071328296758253023455821491848
0960748972838900637634215694097683599029436416

Add the digits in each of those and they add up to 666