666

In the Bible, the Book of Revelation (13:17-18) cryptically asserts 666 to be "the number of a man," associated with the beast, an antagonistic creature that appears briefly about two-thirds into the apocalyptic vision. The calculation of the number was a challenge that has inspired many would-be mystics and prophets ever since. And,

• 666 is the magic sum, or sum of the magic constants of a six by six magic square, any row or column of which adds up to 111.
• The sum of all the numbers on a roulette wheel is 666.
• 666 was a winning lottery number in the 1980 Pennsylvania Lottery scandal, in which equipment was tampered to favour a 4 or 6 as each of the three individual random digits.
• 666 was the original name of the Macintosh SevenDust computer virus that was discovered in 1998.
• In the Bible, 666 is the number of Adonikam's descendants who return to Jerusalem and Judah from the Babylonian exile (see Ezra 2:13).
• In the Bible, 666 is the number of gold talents that King Solomon collected in a single year (see 1 Kings 10:14 and 2 Chronicles 9:13).
• The number 666 is a frequent visual element of Aryan Brotherhood tattoos.

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Source: www.wikipedia.org