179 (number)

← 178 179 180 →
Cardinalone hundred seventy-nine
Ordinal179th
(one hundred seventy-ninth)
Factorizationprime
Prime41st
Divisors1, 179
Greek numeralΡΟΘ´
Roman numeralCLXXIX
Binary101100112
Ternary201223
Senary4556
Octal2638
Duodecimal12B12
HexadecimalB316

179 (one hundred [and] seventy-nine) is the natural number following 178 and preceding 180.

In mathematics

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179 is part of the Cunningham chain of prime numbers 89, 179, 359, 719, 1439, 2879, in which each successive number is two times the previous number, plus one. Among Cunningham chains of this length, this one has the smallest numbers. Because 179 is neither the start nor the end of this chain, it is both a safe prime and a Sophie Germain prime.[1] It is also a super-prime number, because it is the 41st smallest prime and 41 is also prime. Since 971 (the digits of 179 reversed) is prime, 179 is an emirp.

In other fields

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Astronomers have suggested that sunspot frequency undergoes a cycle of approximately 179 years in length.[2]

See also

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References

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  1. ^ Wells, David (1997). The Penguin Dictionary of Curious and Interesting Numbers. Penguin. p. 115. ISBN 9780140261493.
  2. ^ Cohen, Theodore J.; Lintz, Paul R. (August 1974). "Long term periodicities in the sunspot cycle". Nature. 250 (5465): 398–400. Bibcode:1974Natur.250..398C. doi:10.1038/250398a0. S2CID 4181720.
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