173 (number)

173 (one hundred [and] seventy-three) is the natural number following 172 and preceding 174.

In mathematics

• 173 is an odd number, a deficient number, and an odious number. It is a balanced prime, an Eisenstein prime with no imaginary part, and a Sophie Germain prime. It is also an inconsummate number.

173 is the sum of 2 squares: . It is also the sum of three consecutive prime numbers: 53 + 59 + 61.

In astronomy

• 173 Ino is a large dark main belt asteroid
• 173P/Mueller is a periodic comet in our solar system
• Arp 173 (VV 296, KPG 439) is a pair of galaxies in the constellation Boötes

In the military

• 173rd Air Refueling Squadron unit of the Nebraska Air National Guard
• 173rd Airborne Brigade Combat Team of the United States Army based in Vicenza
• 173rd Battalion unit of the Canadian Expeditionary Force during the World War I
• 173rd Surveillance Squadron (Australia) of the Australian Army at Oakey, Queensland
• K-173 Chelyabinsk Russian Oscar class SSGN submarine at the Rybachiy Nuclear Submarine Base in Vilyuchinsk
• USNS Provo (T-AG-173) was a U.S. Navy Phoenix-class auxiliary ship following World War II
• USS Codington (AK-173) was a U.S. Navy Alamosa-class cargo ship during World War II
• USS Eldridge (DE-173) was a U.S. Navy Cannon-class destroyer escort during World War II
• USS Etamin (IX-173) was a U.S. Navy Crater-class cargo ship during World War II
• USS Florence (SP-173) was a U.S. Navy yacht during World War I
• USS Hyde (APA-173) was a U.S. Navy Haskell-classattack transport ship during World War II
• USS PC-472 was a 173-foot (53 m) U.S. Navy submarine chaser during World War II
• USS Pike (SS-173) was a U.S. Navy Porpoise class submarine diesel-electric submarine during World War II
• USS Sproston (DD-173) was a U.S. Navy Wickes class destroyer following World War II
• Vought V-173 (Flying Pancake) was a U.S. Navy experimental test aircraft during World War II

In transportation

• The Georgia Railroad, the world longest railroad in 1845, ran for 173 miles (278 km) from Augusta to Marthasville (Atlanta, Georgia)
• United Airlines Flight 173 en route from Denver to Portland crashed on December 28, 1978
• The Velocity 173 was a kit aircraft produced by Velocity Aircraft in the early '90s.

In other fields

173 is also:

• The year AD 173 or 173 BC
• 173 AH is a year in the Islamic calendar that corresponds to 789 – 790 CE
• The atomic number of an element temporarily called Unsepttrium
• The book "173 Hours in Captivity" (2000)

See also

• List of highways numbered 173
• United Nations Security Council Resolution 173
• United States Supreme Court cases, Volume 173

External links

Wikimedia Commons has media related to 173 (number).

• Number Facts and Trivia: 173
• Prime curiosities: 173
• Number Gossip: 173
• The Number 173