169 (number)
| ||||
|---|---|---|---|---|
| Cardinal | one hundred sixty-nine | |||
| Ordinal | 169th (one hundred sixty-ninth) | |||
| Factorization | 132 | |||
| Divisors | 1, 13, 169 | |||
| Greek numeral | ΡΞΘ´ | |||
| Roman numeral | CLXIX | |||
| Binary | 101010012 | |||
| Ternary | 200213 | |||
| Senary | 4416 | |||
| Octal | 2518 | |||
| Duodecimal | 12112 | |||
| Hexadecimal | A916 | |||
169 (one hundred [and] sixty-nine) is the natural number following 168 and preceding 170.
In mathematics
[edit]169 is an odd number, a composite number, and a deficient number.
169 is a square number: 13 × 13 = 169, and if each number is reversed the equation is still true: 31 × 31 = 961. 144 shares this property: 12 × 12 = 144, 21 × 21 = 441.
169 is one of the few squares to also be a centered hexagonal number.[1] Like all odd squares, it is a centered octagonal number. 169 is an odd-indexed Pell number, thus it is also a Markov number, appearing in the solutions (2, 169, 985), (2, 29, 169), (29, 169, 14701), etc. 169 is the sum of seven consecutive primes: 13 + 17 + 19 + 23 + 29 + 31 + 37. 169 is a difference in consecutive cubes, equaling
In astronomy
[edit]- 169 Zelia is a bright main belt asteroid
- Gliese 169 is an orange, main sequence (K7 V) star in the constellation Taurus
- QSO B0307+169 is a quasar in the constellation Aries
- Sayh al Uhaymir 169 is a 206g lunar meteorite found in Sultanate of Oman
In the military
[edit]- USNS Private Jose F. Valdez (T-AG-169) was a United States Navy technical research ship during the 1960s
- USS Chatham (AK-169) was a United States Navy Alamosa-class cargo ship during World War II
- USS Gallatin (APA-169) was a United States Navy Haskell-class attack transport during World War II
- USS Foote (DD-169) was a United States Navy Wickes-class destroyer following World War I
- USS Atherton (DE-169) was a United States Navy Cannon-class destroyer escort during World War II
- USS Dolphin (SS-169) was a United States Navy submarine during World War II
- 169th Battalion, CEF unit in the Canadian Expeditionary Force during the World War I
- 169th Fires Brigade the US Army National Guard artillery brigade, a part of the Colorado Army National Guard
- The United States Air Force's 169th Fighter Wing fighter unit at McEntire Joint National Guard Station, South Carolina
- 169 or 169th Squadrons
- 169th Airlift Squadron, a unit of the U.S. Air Force
- Marine Light Attack Helicopter Squadron 169, United States Marine Corps Light Attack Helicopter Squadron
- No. 169 Squadron RAF, a unit of the United Kingdom Royal Air Force
In transportation
[edit]- Metro Transit Route 169 in Seattle[2]
- 169th Street station on the IND Queens Boulevard Line of the New York City Subway served by the E and F trains
- 169th Street was a station on the demolished IRT Third Avenue Line of the New York City Subway
In TV and radio
[edit]- The IEC 169-2 connector TV aerial plug
In other fields
[edit]169 is also:
- The year AD 169 or 169 BC
- The atomic number of an element temporarily called Unhexennium[3]
- 169 is the number of nonequivalent starting hands in the card game Texas hold 'em
- 169 is known in the computing world as the first number of an automatic IPv4 address assigned by TCP/IP when no external networking device is contactable
- Minuscule 169 is a Greek minuscule manuscript of the New Testament, on parchment
See also
[edit]- List of highways numbered 169
- United States Supreme Court cases, Volume 169
- United Nations Security Council Resolution 169
- St. Joseph Community Consolidated School District 169
References
[edit]- ^ "Sloane's A003215 : Hex (or centered hexagonal) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-28.
- ^ "Metro Route 169 Timetable, Weekday". transit.metrokc.gov. Archived from the original on 2 October 2002. Retrieved 13 January 2022.
- ^ "FLW Incorporated | Specialists in Physical Measurement, Testing, Calibration & Control".
External links
[edit]
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