666 (number)


666 is the natural number following 665 and preceding 667.
In Christianity, 666 is referred to in most manuscripts of chapter 13 of the Book of Revelation of the New Testament as the "number of the beast" or "number of man".

In mathematics

666 is the sum of the first thirty-six natural numbers, which makes it a triangular number:
In fact, 666 is the largest triangular number that is also a repdigit.
Since 36 is a triangular number too, 666 is a doubly triangular number. Also, 666 is the sum of squares of two consecutive Triangular numbers.
T = 152 + 212,
which can be re-written as:
T = 2 + 2
TT5+TT3 = 2 + 2.
The difference of 21² and 15² is:
216 = 6 × 36 or 6 × 6 × 6,
Which can be expressed:
216 = (T3) × (T3)² or (TT2) × (TT2)².
666 is a congruent number, as it is possible to make a right triangle with rationally numbered side lengths whose area is 666.
The number of integers which are relatively prime to 666 is 216, ; and for an angle measured in degrees, .
666 is also the sum of the squares of the first seven primes, while the number of twin primes less than is 666.
A prime reciprocal magic square based on in decimal has a magic constant of 666. The twelfth pair of twin primes is, with 151 the thirty-sixth prime number.
666 is a Smith number and Harshad number in base ten. The 27th indexed unique prime in decimal features a "666" in the middle of its sequence of digits.
The Roman numeral for 666, DCLXVI, has exactly one occurrence of all symbols whose value is less than 1000 in decreasing order.

In Christian religion

Number of the beast

Image:Inferno Canto 34.jpg|thumb|666 is often associated with Satan, who is illustrated here in an engraved interpretation by Gustave Doré.
In the Textus Receptus manuscripts of the New Testament, the Book of Revelation cryptically asserts 666 to be "the man's number" or "the number of a man" associated with the Beast, an antagonistic creature that appears briefly about two-thirds into the apocalyptic vision. Some manuscripts of the original Koine Greek use the symbols χξϛ chi xi stigma, while other manuscripts spell out the number in words.
In modern popular culture, 666 has become one of the most widely recognized symbols for the Antichrist or, alternatively Satanism. Earnest references to the number occur both among apocalypticist Christian groups and in explicitly anti-Christian subcultures.
References in contemporary Western art or literature are, more likely than not, intentional references to the Beast symbolism. Such popular references are therefore too numerous to list.
It is common to see the symbolic role of the integer 666 transferred to the numerical digit sequence 6-6-6. Some people take the Satanic associations of 666 so seriously that they actively avoid things related to 666 or the digits 6-6-6. This is known as hexakosioihexekontahexaphobia.
There is a broad consensus in contemporary scholarship that the number of the beast refers to the Roman emperor Nero, who reigned from 55 to 68 AD. The Greek version of his name transliterates into Hebrew as נרון קסר, and, using gematria, yields a numerical value of 666. His Latin name, "Nero Caesar", transliterated as נרו קסר, produces the number 616 instead, which is also cited as the Number of the Beast in some early biblical manuscripts.

Other occurrences

In other fields

[Image:666parade.jpeg|thumb|A 666 float in a Paris street parade]The Number of the Beast, the 1982 album by English heavy metal band Iron Maiden, references 666 in its title and the album's title song.