{{Infobox number | number = 70 | factorization=2 x 5 x 7 | divisor = 1, 2, 5, 7, 10, 14, 35, 70 | lang1 = Hebrew | lang1 symbol = <span style="font-size:150%;">ע</span> | lang2 = Lao | lang2 symbol = <span style="font-size:127%;">໗</span> | lang3=Armenian|lang3 symbol=Հ | lang4=Babylonian numeral|lang4 symbol=𒐕𒌋 | lang5=Egyptian hieroglyph|lang5 symbol=<span style="font-size:300%;">𓎌</span> }}
'''70''' ('''seventy''') is the natural number following 69 and preceding 71.
== Mathematics == 70 is a composite number, an Erdős–Woods number<ref>{{cite web |title=Sloane's A059756 : Erdős-Woods numbers |url=https://oeis.org/A059756 |access-date=2016-05-29 |website=The On-Line Encyclopedia of Integer Sequences |publisher=OEIS Foundation}}</ref>, a Pell number, a central binomial coefficient<ref>{{Cite OEIS|A000984|Central binomial coefficients: binomial(2*n,n) as (2*n)!/(n!)^2.}}</ref>, and a primitive abundant number. 70 is the smallest weird number, which is a natural number that is abundant but not semiperfect.<ref>{{cite web|title=Sloane's A006037 : Weird numbers|url=https://oeis.org/A006037|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-05-29}}</ref>
70 is also part of the only nontrivial solution pair to the cannonball problem, along with 24.
== In religion == * In Jewish tradition, Ptolemy II Philadelphus ordered 72 Jewish elders to translate the Torah into Greek; the result was the Septuagint (from the Latin for "seventy"). The Roman numeral seventy, LXX, is the scholarly symbol for the Septuagint.
* In Islamic history and in Islamic interpretation the number 70 or 72 is most often and generally hyperbole for an infinite amount: ** There are 70 dead among Muhammad's adversaries during the Battle of Badr. ** 70 of Muhammad's followers are martyred at the Battle of Uhud. ** In Shia Islam, there are 70 martyrs among Imam Hussein's followers during the Battle of Karbala.
== In other fields == * In some traditions, 70 years of marriage is marked by a platinum wedding anniversary. * Under Social Security (United States), the age at which a person can receive the maximum retirement benefits (and may do so and continue working without reduction of benefits).
== Number name == {{Main article|Numeral (linguistics)}} {{Wiktionary|seventy}}
Several languages, especially ones with vigesimal number systems, do not have a specific word for 70: for example, {{Langx|fr|soixante-dix|lit=sixty-ten}}; {{Langx|da|halvfjerds}}, short for {{Langx|da|halvfjerdsindstyve|lit=three and a half score|label=none}}. (For French, this is true only in France, Canada and Luxembourg; other French-speaking regions such as Belgium, Switzerland, Aosta Valley and Jersey use {{Lang|fr|septante}}.)<ref>Peter Higgins, ''Number Story''. London: Copernicus Books (2008): 19. "Belgian French speakers however grew tired of this and introduced the new names septante, octante, nonante etc. for these numbers".</ref>
== Notes == {{Notelist}}
== References == <!--This article uses the Cite.php citation mechanism. If you would like more information on how to add references to this article, please see http://meta.wikimedia.org/wiki/Cite/Cite.php --> {{Reflist}}
== External links == {{Integers|zero}} {{Authority control}}
{{DEFAULTSORT:70 (Number)}} Category:Integers