66 (sixty-six) is the natural number following 65 and preceding 67.
Usages of this number include:
66 is:
a sphenic number.
a triangular number.
a hexagonal number.
a semi-meandric number.
a semiperfect number, being a multiple of a perfect number.
an Erdős–Woods number, since it is possible to find sequences of 66 consecutive integers such that each inner member shares a factor with either the first or the last member.
palindromic and a repdigit in bases 10 (6610), 21 (3321) and 32 (2232)
a Harshad number in bases 2, 4, 5, 6, 7, 8, 11, 12, 13 and 16.
Messier object Spiral Galaxy M66, a magnitude 10.0 galaxy in the constellation Leo.
The New General Catalogue object NGC 66, a peculiar barred spiral galaxy in the constellation Cetus.
The Saros number of the solar eclipse series which began on 12 March -756 and ended on 1 May 542. The duration of Saros series 66 was 1298.1 years, and it contained 73 solar eclipses.
The Saros number of the lunar eclipse series which began on 12 August -671 and ended on 27 January 826. The duration of Saros series 66 was 1496.5 years, and it contained 84 lunar eclipses.
The atomic number of dysprosium, a lanthanide.
66 (more specifically 66.667) megahertz (MHz) is a common divisor for the front side bus (FSB) speed, overall central processing unit (CPU) speed, and base bus speed. On a Core 2 CPU, and a Core 2 motherboard, the FSB is 1066 MHz (~16 × 66 MHz), the memory speed is usually 666.67 MHz (~10 × 66 MHz), and the processor speed ranges from 1.86 gigahertz (GHz) (~66 MHz × 28) to 2.93 GHz (~66 MHz × 44), in 266 MHz (~66 MHz × 4) increments.
The designation of the historic U.S. Route 66, dubbed the "Mother Road" by novelist John Steinbeck.
The designation of US Interstate 66, a freeway that runs from Virginia to Washington, D.C.
The designation of 36 US state and 2 territorial highways (see list of highways numbered 66).
Phillips 66, a brand of gasoline and service station in the United States.
The total number of chapters in the Bible book of Isaiah.
The number of verses in Chapter 3 of the book of Lamentations in the Old Testament.
The total number of books in the Protestant edition of the Bible (Old Testament and New Testament) combined.
In Abjad numerals, The Name Of Allah (الله) numeric value is 66.
The Green Bay Packers of the National Football League retired jersey number 66 for linebacker Ray Nitschke. The last Packer to wear number 66 before it was retired in 1983 to honor Nitschke was offensive tackle Larry Pfohl, who is better known to professional wrestling fans as Lex Luger.
Jersey number 66 was retired by the Pittsburgh Penguins of the National Hockey League in honor of Mario Lemieux.
Sixty Six (film) is a 2006 British movie about a bar mitzvah in London on the day of the 1966 World Cup final.
In the Star Wars movie series, Order 66 is a prepared order to the clone troopers to kill the Jedi commanding them.
Route 66 was a popular US television series on CBS from 1960 to 1964.
In the video game Fullmetal Alchemist, elusive villain Barry the Chopper is imprisoned in cell number 66, which later becomes his alias when battling the brothers at Laboratory Five.
The international direct dialing (IDD) code for Thailand.
The number of the French department Pyrénées-Orientales.
Municipal Okrug #66, name of Chyornaya rechka Municipal Okrug of Primorsky District of Saint Petersburg, Russia, until 2008.
The name of a German card game, translated from sechsundsechzig.
The name of a card game derived from the German card game, Sixty-six (game).
In Telecommunications a 66 block is used to organize telephone lines.
66 is the number of hot dogs eaten by World record holder Joey Chestnut in 15 minutes at the Nathan's Hot Dog Eating Contest in 2007.
Sergio Mendes and Brazil '66 was a 1960s group.
66 WNBC radio was a popular New York radio station, which became WFAN on 1 July 1987.
Lil B has a song entitled OMG 66.
Le 66 is an opérette in one act of 1856 with music by Jacques Offenbach and a French libretto by Pittaud de Forges and Laurencin.
In the horror genre and western esotericism there are 66 legions of demons/spirits that Baal controls.
