|Cardinal||one hundred seventy-nine|
(one hundred seventy-ninth)
179 (one hundred [and] seventy-nine) is the natural number following 178 and preceding 180.
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.
Astronomers have suggested that sunspot frequency undergoes a cycle of approximately 179 years in length.