86 (eighty-six) is the
natural number
In mathematics, the natural numbers are those numbers used for counting (as in "there are ''six'' coins on the table") and ordering (as in "this is the ''third'' largest city in the country").
Numbers used for counting are called '' cardinal ...
following
85 and preceding
87.
In mathematics
86 is:
*
nontotient
In number theory, a nontotient is a positive integer ''n'' which is not a totient number: it is not in the range of Euler's totient function φ, that is, the equation φ(''x'') = ''n'' has no solution ''x''. In other words, ''n'' is a nontotien ...
and a
noncototient In mathematics, a noncototient is a positive integer ''n'' that cannot be expressed as the difference between a positive integer ''m'' and the number of coprime integers below it. That is, ''m'' − φ(''m'') = ''n'', where Ï ...
.
* the 25th distinct
semiprime
In mathematics, a semiprime is a natural number that is the product of exactly two prime numbers. The two primes in the product may equal each other, so the semiprimes include the squares of prime numbers.
Because there are infinitely many prime ...
and the 13th of the form (2×q).
* an
Erdős–Woods number, since it is possible to find sequences of 86 consecutive integers such that each inner member shares a factor with either the first or the last member.
* a
happy number
In number theory, a happy number is a number which eventually reaches 1 when replaced by the sum of the square of each digit. For instance, 13 is a happy number because 1^2+3^2=10, and 1^2+0^2=1. On the other hand, 4 is not a happy number because ...
and a
self number in base 10.
It appears in the
Padovan sequence
In number theory, the Padovan sequence is the sequence of integers ''P''(''n'') defined. by the initial values
:P(0)=P(1)=P(2)=1,
and the recurrence relation
:P(n)=P(n-2)+P(n-3).
The first few values of ''P''(''n'') are
:1, 1, 1, 2, 2, 3, ...
, preceded by the terms 37, 49, 65 (it is the sum of the first two of these).
It is
conjecture
In mathematics, a conjecture is a conclusion or a proposition that is proffered on a tentative basis without proof. Some conjectures, such as the Riemann hypothesis (still a conjecture) or Fermat's Last Theorem (a conjecture until proven in ...
d that 86 is the largest n for which the
decimal expansion
A decimal representation of a non-negative real number is its expression as a sequence of symbols consisting of decimal digits traditionally written with a single separator:
r = b_k b_\ldots b_0.a_1a_2\ldots
Here is the decimal separator, ...
of 2
n contains no 0.
86 = (8 × 6 = 48) + (4 × 8 = 32) + (3 × 2 = 6). That is, 86 is equal to the sum of the numbers formed in calculating its
multiplicative persistence.
In science
* 86 is the
atomic number
The atomic number or nuclear charge number (symbol ''Z'') of a chemical element is the charge number of an atomic nucleus. For ordinary nuclei, this is equal to the proton number (''n''p) or the number of protons found in the nucleus of ever ...
of
radon
Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colourless, odourless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains th ...
.
* There are 86 metals on the modern
periodic table
The periodic table, also known as the periodic table of the (chemical) elements, is a rows and columns arrangement of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of ch ...
.
In other fields
*In American English, and particularly in the food service industry,
86 has become a slang term referring to an item being out of stock or discontinued, and by extension to a person no longer welcome on the premises.
*The number of the French department
Vienne. This number is also reflected in the department's
postal code
A postal code (also known locally in various English-speaking countries throughout the world as a postcode, post code, PIN or ZIP Code) is a series of letters or digits or both, sometimes including spaces or punctuation, included in a postal ...
and in the name of a local basketball club,
Poitiers Basket 86
Poitiers Basket 86, also known as PB86 or simply Poitiers, is a French professional basketball team located in the city of Poitiers, in the Nouvelle-Aquitaine region, France. It competes in the French Pro B league. The club's home games are pla ...
.
*
+86 is the
code for international direct dial
Country calling codes or country dial-in codes are telephone number prefixes for reaching telephone subscribers in the networks of the member countries or regions of the International Telecommunication Union (ITU). The codes are defined by the ...
phone calls to
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...
.
*An art gallery in Ventura, California, displaying art pieces from such artists
Billy Childish
Billy Childish (born Steven John Hamper, 1 December 1959) is an English painter, author, poet, photographer, film maker, singer and guitarist. Since the late 1970s, Childish has been prolific in creating music, writing and visual art. He has le ...
,
Stacy Lande and
Derek Hess, most of which include the number *86 hidden or overtly shown in the art, and some of which fall under the genre of
lowbrow.
*86 is the
device number for a lockout relay function in
electrical engineering
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
electrical circuit protection schemes.
*86 is often used in Japan as the nickname for the
Toyota AE86
The AE86 series of the Toyota Corolla Levin and Toyota Sprinter Trueno are small, front-engine/rear-wheel-drive models within the front-engine/front-wheel-drive fifth generation Corolla (E80) range—marketed by Toyota from 1983 to 1987 in co ...
.
*
''86'' is the name of a series of Japanese science fiction
light novels
A light novel (, Hepburn: ''raito noberu'') is a style of young adult novel primarily targeting high school and middle school students. The term "light novel" is a '' wasei-eigo'', or a Japanese term formed from words in the English languag ...
written by
Asato Asato
is a female Japanese novelist. The pen name Asato Asato is a combination of her real name (Toru Asakura) and eighty-eight.
Career
Asato started writing novels just before she entered junior high school.
She initially submitted her work to th ...
, later adapted as a manga and an anime.
See also
*
List of highways numbered 86
Notes
{{DEFAULTSORT:86 (Number)
Integers