161 (number)

From Wikipedia, the free encyclopedia

List of numbers — Integers << 160 161 162 163 164 165 166 167 168 169 >>
Cardinal	one hundred and sixty-one
Ordinal	161st (one hundred and sixty-first)
Factorization
Divisors	1, 7, 23, 161
Roman numeral	CLXI
Binary	10100001
Hexadecimal	A1

161 is an odd natural number between 160 and 162. It is the sum of five consecutive prime numbers, namely 23, 29, 31, 37, and 41. 161 is also a hexagonal pyramidal number.

161 is a semiprime: a product of two prime numbers, namely 7 and 23. Since those prime factors are Gaussian primes, this means that 161 is a Blum integer.

[edit] In travel and geography

• 161 kilometers is equal to 100 miles.
• The double-landlocked country of Liechtenstein has a land area of 161 square kilometers.
• When the countries of the world are listed alphabetically Northern Cyprus is 161st. Also Nicosia the capital city of Northern Cyprus (and the Republic of Cyprus) is 161 meters above sea level.
• The countries of Bahrain and Brunei both have coastlines that are 161 kilometers in length.