666 is a natural number after 665 and before 667. It is a number with many properties. One of these properties is that it is the sum of the first 36 natural numbers. That makes 666 a triangular number. 666 is the sum of the first 144 decimals (digits after the decimal point) of pi. The number is also used in the 666 dating rule or rule of sixes which judges the attractiveness of men.
|Cardinal||six hundred sixty-six|
(six hundred sixty-sixth)
|Factorization||2 × 32× 37|
The Bible says in the Book of Revelation that the number 666 is associated with the Antichrist, the "Number of the Beast". People will be forced to accept this number as a mark on the penalty of death if they refuse. However, people who do accept this mark will be rejected by God.