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==In mathematics==
135 is the number of [[integer partition]]s of [[14 (number)|14]], and the number of rooted trees with [[15 (number)|15]] nodes and height at most 2.<ref name="partitions">{{Cite OEIS |A000041 |The number of partitions of n (the partition numbers) |access-date=2022-12-05 }}</ref> 135 is 5-[[Smooth number|smooth]], since its prime factorization is <math>3^3 \times 5</math>, and a [[Harshad number]] in [[decimal]].<ref>{{Cite OEIS |A005349 |Niven (or Harshad, or harshad) numbers: numbers that are divisible by the sum of their digits. |access-date=2022-12-05 }}</ref><ref>{{Cite OEIS |A051037 |5-smooth numbers, i.e., numbers whose prime divisors are all less than or equal to five. |access-date=2022-12-05 }}</ref>
This number in [[base 10]] can be expressed in operations using its own digits in at least two different ways. One is as a [[sum-product number]],▼
▲
:<math>135
:<math>135 = (1 + 3 + 5)(1 \times 3 \times 5)</math><ref>{{Cite web|url=https://oeis.org/A038369|title=Sloane's A038369 : Numbers n such that n = (product of digits of n) * (sum of digits of n)|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-27}}</ref>
135 is the number of degrees in the [[internal angle]] of a regular eight-sided [[octagon]], and the number of [[Vertex (graph theory)|nodes]] inside a regular [[nonagon]] from the intersection of its [[diagonal]]s and [[Edge (geometry)|sides]].<ref>{{Cite OEIS |A007569 |Number of nodes in regular n-gon with all diagonals drawn. |access-date=2023-04-04 }}</ref> Also:
*the [[Euler's totient function|Euler totient]] of 135 is [[72 (number)|72]]: the degrees of a [[central angle]] in a regular [[pentagon]].<ref>{{Cite OEIS |A000010 |Euler totient function phi(n): count numbers less than or equal to ''n'' and prime to ''n''. |access-date=2022-12-06 }}</ref>
*the [[arithmetic mean]] of the divisors of 135 is [[30 (number)|30]]: the degrees in a central angle of a regular [[dodecagon]].
While the central angle of a regular octagon is 135 '''÷''' 3 = 45 degrees, 4.5 is the [[harmonic mean]] of all '''eight''' divisors of 135.
The [[aliquot sum]] of 135 is [[105 (number)|105]], which is the 14th [[triangular number]], or equivalently the sum of the first fourteen non-zero positive [[integer]]s.<ref>{{Cite OEIS |A001065 |Sum of proper divisors (or aliquot parts) of n: sum of divisors of n that are less than n. |access-date=2022-12-06 }}</ref><ref>{{Cite OEIS |A000217 |Triangular numbers |access-date=2022-12-06 }}</ref>
There are 135 total ''Krotenheerdt'' [[Euclidean tilings by convex regular polygons#k-uniform tilings|''k''-uniform]] tilings for ''k'' < 8, with no other such tilings for higher ''k''.<ref>{{Cite OEIS |A068600 |Number of n-uniform tilings having n different arrangements of polygons about their vertices. |access-date=2023-01-09 }}</ref>
▲135 is a [[Harshad number]].<ref>{{Cite web|url=https://oeis.org/A005349|title=Sloane's A005349 : Niven (or Harshad) numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-27}}</ref>
There are a total of 135 [[prime number|primes]] between [[1000 (number)|1,000]] and [[2000 (number)|2,000]].
<math>135 = 11 n^2 + 11 n + 3</math> for <math>n = 3</math>
* [[OC-135B Open Skies]] United States Air Force observation aircraft supports the flies unarmed observation flights over nations of the [[Treaty on Open Skies]]▼
==In other fields==
* The year [[AD 135]] or [[135 BC]].
* 135 AH is a year in the [[Islamic calendar]] that corresponds to 752
* [[135 Hertha]] is a large [[main belt]] [[asteroid]] which orbits among the [[Nysa family|Nysa]] asteroid family.
* [[135 film]], the cartridge version of 35mm photographic film, used widely in still photography.
* The [[Canon
* In [[astrology]], when two planets are 135 degrees apart, they are in an [[astrological aspect]] called a sesquiquadrate. The aspect was first used by [[Johannes Kepler]].
* [[Sonnet 135]] by [[William Shakespeare]].
* [[Municipal District of Peace No. 135]], a [[municipal district]] in northwest [[Alberta]], Canada.
* [[Enoch Cree Nation 135]] [[Indian reserve]] in Alberta, Canada, is home to the [[Enoch Cree Nation]].
* The [[EZ 135 Drive]] removable [[Hard drive|hard disk drive]] introduced by [[SyQuest Technology]] in 1995.
▲* [[OC-135B Open Skies]] United States Air Force observation aircraft
== See also ==
{{Commons category
* [[List of highways numbered 135]]
* [[United Nations Security Council Resolution 135]]
* [[List of United States Supreme Court cases, volume
== References ==
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