133 (one hundred [and] thirty-three) is the natural number following 132 and preceding 134.

133 is an n whose divisors (excluding n itself) added up divide φ(n). It is an octagonal number^[1] and a happy number.^[2]

133 is a Harshad number, because it is divisible by the sum of its digits.

133 is a repdigit in base 11 (111) and base 18 (77), whilst in base 20 it is a cyclic number formed from the reciprocal of the number three.

133 is a semiprime: a product of two prime numbers, namely 7 and 19. Since those prime factors are Gaussian primes, this means that 133 is a Blum integer.

133 is the number of compositions of 13 into distinct parts.^[3]

• Douglas C-133 Cargomaster was a United States cargo aircraft built between 1956 and 1961
• HMAS Betano (L 133) is a Balikpapan-class heavy landing craft which launched in 1972
• USNS Mission Santa Cruz (T-AO-133) was a United States Navy Mission Buenaventura-class fleet oilers during World War II
• USS Beckham (APA-133) was a United States Navy Haskell-class attack transport during World War II
• USS Burdo (APD-133) was a United States Navy Crosley-class high speed transport during World War II
• USS General O. H. Ernst (AP-133) was a United States Navy General G. O. Squier-class transport ship during World War II
• USS Hale (DD-133) was a United States Navy Wickes-class destroyer during World War I
• USS Hawk (AM-133) was a United States Navy Hawk-class minesweeper during World War II
• USS Pillsbury (DE-133) was a United States Navy Edsall-class destroyer escort during World War II
• USS S-28 (SS-133) was a United States Navy S-class submarine during World War II
• USS Seginus (AK-133) was a United States Navy Crater-class cargo ship during World War II
• USS Toledo (CA-133) was a United States Navy Baltimore-class heavy cruiser during the Korean War
• Frontstalag 133 was a temporary German prisoner of war camp during World War II located near Rennes, northern France
• Caproni Ca.133 was a three-engine transport/bomber aircraft used by the Italian Regia Aeronautica from the Second Italo-Abyssinian War until World War II
• Naval Mobile Construction Battalion 133 is an active duty Seabee battalion originally commissioned during World War II as the 133rd Naval Construction Battalion(NCB)

• London Buses route 133 is a Transport for London contracted bus route in London
• RATB route 133 is bus route run by RATB in Bucharest, Romania
• The Fiat 133, also called SEAT 133, was a small rear-engine car developed in Spain between 1974 and 1979
• STS-133 is a Space Shuttle Endeavour contingency mission which was Discovery's 39th and final mission. The mission launched on 24 February 2011, and landed on 9 March 2011.
• The Bücker Bü 133 Jungmeister was a single-engine, single-seat biplane trainer of the Luftwaffe in the 1930s

133 is also:

• The nickname of Craig Jones
• The year AD 133 or 133 BC
• 133 AH is a year in the Islamic calendar that corresponds to 750 – 751 CE
• 133P/Elst-Pizarro is a body with characteristics of both asteroids and comets, a prototype of main-belt comets
• 133 Cyrene is an S-type main belt asteroid
• The atomic number of an element temporarily called untritrium.
• Xenon-133 is an isotope of xenon. It is a radionuclide that is inhaled to assess pulmonary function, and to image the lungs
• 133 is the police emergency telephone number in Chile
• "133" is the name of a David Guetta song, from the album Just a Little More Love (perhaps because it is a happy number)
• Cosmos 133 was a Soviet Soyuz programme test satellite launched from the Baikonur cosmodrome aboard a Vostok rocket in 1966
• PC133 is a computer memory standard defined by the JEDEC
• FASB 133 is a Statements of Financial Accounting Standards No. 133, Accounting for Derivative Instruments and Hedging Activities, an accounting standard issued in 2001 by the Financial Accounting Standards Board that provides companies with the ability to measure assets and liabilities
• OMB A-133 Compliance Supplement is a guide created by the Office of Management and Budget (OMB) for auditing United States Federal assistance and Federal grants
• The 2006 film 133 Skyway starring Terry Barnhart from Big Soul Productions Inc.
• Sonnet 133 by William Shakespeare
• The Municipal District of Spirit River No. 133 is a municipal district in northwest Alberta, Canada, north of Grande Prairie
• In Austria, the phone number for the police.^[4]

• List of highways numbered 133
• United Nations Security Council Resolution 133
• United States Supreme Court cases, Volume 133