105 Cardinal one hundred [and] five Ordinal 105th
(one hundred [and] fifth)
Numeral system 105 Factorization Divisors 1, 3, 5, 7, 15, 21, 35, 105 Roman numeral CV Binary 11010012 Octal 1518 Duodecimal 8912 Hexadecimal 6916
105 is a triangular number, a 12-gonal number and a Zeisel number. It is a sphenic number, and is the product of three consecutive prime numbers. 105 is the double factorial of 7. It is also the sum of the first five square pyramidal numbers.
105 comes in the middle of the prime quadruplet (101, 103, 107, 109). The only other such odd numbers less than a thousand are 15, 195 and 825. 105 is also a pseudoprime to the prime bases 13, 29, 41, 43, 71, 83 and 97. The distinct prime factors of 105 add up to 15, and so do those of 104, hence the two numbers form a Ruth-Aaron pair under the first definition.
105 is also a number n for which n − 2k is prime, for 0 < k < log2(n). (This even works up to k = 8, ignoring the negative sign.)
105 is the smallest integer such that the factorization of xn − 1 over Q includes coefficients other than .
In other fields
105 is also:
- The number of surat al-Fil in the Qur'an.
- A simple card game where players lose if they have over 105 points.
- Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London: Penguin Group. (1987): 134
Wikimedia Foundation. 2010.
Look at other dictionaries:
Number One (1969 film) — Number One Directed by Tom Gries Produced by Walter Seltzer Written by David Moessinger Starring Charlton Heston … Wikipedia
Number of Westminster MPs — Over the history of the House of Commons, the number of Members of Parliament (MPs) has varied for assorted reasons, with increases in recent years due to increases in the population of the United Kingdom. There are currently 650 constituencies,… … Wikipedia
Number theory — A Lehmer sieve an analog computer once used for finding primes and solving simple diophantine equations. Number theory is a branch of pure mathematics devoted primarily to the study of the integers. Number theorists study prime numbers (the… … Wikipedia
105 mm Howitzer M3 — Infobox Weapon name=105 mm Howitzer M3 caption=A M3 howitzer outside the Army Museum in Honolulu, Hawaii. origin=United States type=Light Howitzer is ranged=1 is bladed= is explosive= is artillery=1 is vehicle= is UK= service=1943 ? used… … Wikipedia
Wikipedia:List of Wikipedians by number of edits — Shortcuts: WP:NOE WP:WBE WP:EDITS WP:MOSTEDITS This is a list of Wikipedians ordered by number of edits in the English language Wikipedia. Edits in all namespaces are counted; deleted edits have been included in recent versions. Click… … Wikipedia
69105 (number) — The number 69,105 was used as an in joke at the United States computer game manufacturer Infocom. It has occasionally appeared in later computer games as a tribute to Infocom.In mathematics69105 is the third 23036 gonal number and the fifth 6912… … Wikipedia
Bundesstraße 105 — Vorlage:Infobox hochrangige Straße/Wartung/DE B Bundesstraße 105 in Deutschland K … Deutsch Wikipedia
CF-105 Arrow — Infobox Aircraft name= CF 105 Arrow type= Interceptor manufacturer= Avro Aircraft Limited (Canada) caption= Photo from the Canadian Department of National Defence designer= first flight= 25 March 1958 introduction= retired= status= Cancelled 20… … Wikipedia
F-105 Thunderchief — Infobox Aircraft name= F 105 Thunderchief type= Fighter bomber manufacturer= Republic Aviation Company caption= A two seat F 105G Wild Weasel, with a 650 US gallon (2,500 l) centerline fuel tank and AGM 45 Shrike anti radiation missiles. designer … Wikipedia
Avro Canada CF-105 Arrow — CF 105 Arrow Photo from the Canadian Department of National Defence Role Interceptor … Wikipedia