666 (number)
From Freepedia
666 is the Number of the Beast in most versions of the Christian Bible, in the Book of Revelation.
| |||
| 666 | |||
|---|---|---|---|
| Cardinal | Six hundred and sixty-six | ||
| Ordinal | 666th | ||
| Factorization | <math>2 \cdot 3^2 \cdot 37</math> | ||
| Roman numeral | DCLXVI | ||
| Binary | 1010011010 | ||
| Hexadecimal | 29A | ||
| Base32 | KQ | ||
| Base36 | II | ||
In mathematics
666 is an abundant number. It is the sum of the squares of the first seven prime numbers.
Since 36 is both square and triangular, 666 is the sixth number of the form <math>n^2(n^2+1)/2</math> (triangular squares) and the eighth number of the form <math>n(n+1)(n^2+n+2)/8</math> (doubly triangular numbers.)
There is no number whose value of Euler's totient function φ is 666, making it a nontotient.
The harmonic mean of the digits of 666 is an integer: 3/(1/6 + 1/6 + 1/6) = 6. 666 is the 54th number with this property.
In base 10, 666 is a palindromic number, a repdigit and a Smith number. A prime reciprocal magic square based on 1/149 in base 10 has a magic total of 666.
The Roman numeral representation of the number 666 (DCLXVI) uses once each of the Roman numeral symbols with values under 1,000, and that they are in exact reverse order of their respective values (D = 500, C = 100, L = 50, X = 10, V = 5, I = 1).
In other fields
- 666 is commonly known as the Number of the Beast in the Book of Revelation.
- On the Microsoft Windows operating system, the key sequence Alt+666 will create a capital U umlaut (Ü).
- 666 is also the value of the kilohertz frequency of the Bodenseesender, a big AM radio station in South Germany, which is receivable at night in all of Europe. It is also the frequency of the Australian Broadcasting Corporation's Canberra station.
- In the United States, 666 is a brand name of cough syrup.
- 666 is the port number used by the game Doom (by id Software) when playing against another player via TCP.
- In UNIX and similar operating systems, file permissions are granted by a triplet of octal numerals, 000 through 777. Each position denotes the group of users for which the permission applies: the first digit for owner, second digit for group, and third digit for all other users. 4 grants read permission; 2 grants write permission; and 1 grants execute permission. Permissions are simply summed for each position. For example, a file permission of 751 would grant the owner of the file the permission to read, write, and execute the file; users in the file owner's group to read and execute the file; and all other users to execute the file only. Thus, a file permission of 666 (which is not uncommon) grants all users read and write permissions on the file. In directory listings (e.g. via the command ls -l), this file permission is also written as -rw-rw-rw- (the first dash meaning the file is not a directory, the first r for owner's read permission, the first w for the owner's write permission, the second dash for non-executable by the owner, the later rw--sequences for group and all respectively).
- Using the web coding language CSS, one may attribute a dark gray color to any web page object using the shorthand hexidecimal format: #666.
- 666 is the sum of all the numbers on a typical roulette wheel. (A typical roulette wheel is numbered from 1 to 36, with one (in Europe) or two (in North America) zeroes. See the point on triangular numbers, above.)
- In 1997, an urban myth of 666 spread around some areas. "Take the number of the beast (666) and multiply it by the number of the next world war (3) to find out when the world will end (1998)."
- CSXT currently has a GE AC60CW with the number 666 and some of the crews do hate that unit.
- 666 is a nickname for Benzene Hexachloride, a powerful insecticide and pediculicide. Its chemical formula is C6H6Cl6.
- Similar to the Roman numeral occurence, combining one of each of Japan's coin currency yields 666 (500 piece, 100, 50, 10, 5, 1)
