257 (two hundred
ndfifty-seven) is the natural number following
256
Year 256 (Roman numerals, CCLVI) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Claudius and Marcus Acilius Glabrio (consul 256), Glab ...
and preceding
258.
In mathematics
257 is a
prime number
A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only way ...
of the form
specifically with ''n'' = 3, and therefore a
Fermat prime
In mathematics, a Fermat number, named after Pierre de Fermat, who first studied them, is a positive integer of the form
:F_ = 2^ + 1,
where ''n'' is a non-negative integer. The first few Fermat numbers are:
: 3, 5, 17, 257, 65537, 4294967 ...
. Thus a
regular
The term regular can mean normal or in accordance with rules. It may refer to:
People
* Moses Regular (born 1971), America football player
Arts, entertainment, and media Music
* "Regular" (Badfinger song)
* Regular tunings of stringed instrum ...
polygon with 257 sides is
constructible with compass and unmarked straightedge. It is currently the second largest known Fermat prime.
Analogously, 257 is the third
Sierpinski prime of the first kind, of the form
➜
.
It is also
a
balanced prime In number theory, a balanced prime is a prime number with equal-sized prime gaps above and below it, so that it is equal to the arithmetic mean of the nearest primes above and below. Or to put it algebraically, given a prime number p_n, where is i ...
,
an
irregular prime
In number theory, a regular prime is a special kind of prime number, defined by Ernst Kummer in 1850 to prove certain cases of Fermat's Last Theorem. Regular primes may be defined via the divisibility of either class numbers or of Bernoulli nu ...
,
a prime that is one more than a square,
and a
Jacobsthal–Lucas number.
There are exactly 257 combinatorially distinct
convex polyhedra
A convex polytope is a special case of a polytope, having the additional property that it is also a convex set contained in the n-dimensional Euclidean space \mathbb^n. Most texts. use the term "polytope" for a bounded convex polytope, and the wor ...
with eight
vertices (or
polyhedral graph
In geometric graph theory, a branch of mathematics, a polyhedral graph is the undirected graph formed from the vertices and edges of a convex polyhedron. Alternatively, in purely graph-theoretic terms, the polyhedral graphs are the 3-vertex-c ...
s with eight nodes).
In other fields
*The years
257 and
257 BC
*257 is the country calling code for
Burundi
Burundi (, ), officially the Republic of Burundi ( rn, Repuburika y’Uburundi ; Swahili: ''Jamuhuri ya Burundi''; French: ''République du Burundi'' ), is a landlocked country in the Great Rift Valley at the junction between the African Gr ...
. See
List of country calling codes
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 ...
.
*
.257 Roberts
The .257 Roberts, also known as .257 Bob, is a medium-powered .25 caliber rifle cartridge. It has been described as the best compromise between the low recoil and flat trajectory of smaller calibers such as the 5 mm (.22") and 6 mm (.24"), and ...
, rifle cartridge
*There is a Pac-Man themed restaurant called
Level 257 located in
Schaumburg, Illinois
Schaumburg ( ) is a village mostly in Cook County and partly in DuPage County in northeastern Illinois, United States. Per the 2020 Census, the population was 78,723. Schaumburg is around northwest of the Chicago Loop and northwest of O'Hare ...
. It is in reference to the
kill screen
''Kill Screen'' (stylized as ''KILL SCREEN'') was a print and online magazine founded in 2009 by Jamin Warren and Chris Dahlen and owned by Kill Screen Media, Inc. It focused on video games and culture, but also included articles based on ente ...
reached in Level 256 in the
Pac-Man
originally called ''Puck Man'' in Japan, is a 1980 maze video game, maze action game, action video game developed and released by Namco for Arcade game, arcades. In North America, the game was released by Midway Manufacturing as part of its l ...
arcade game.
*
257ers is a German hip hop duo
References
{{DEFAULTSORT:257 (Number)
Integers