161 (number)

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← 160 161 162 →
Cardinal one hundred sixty-one
Ordinal 161st
(one hundred sixty-first)
Factorization 7 × 23
Divisors 1, 7, 23, 161
Greek numeral ΡΞΑ´
Roman numeral CLXI
Binary 101000012
Ternary 122223
Quaternary 22014
Quinary 11215
Senary 4256
Octal 2418
Duodecimal 11512
Hexadecimal A116
Vigesimal 8120
Base 36 4H36

161 (one hundred [and] sixty-one) is the natural number following 160 and preceding 162.

In mathematics[edit]

161 is the sum of five consecutive prime numbers: 23, 29, 31, 37, and 41

161 is a hexagonal pyramidal number.[1]

161 is a semiprime. Since its prime factors 7 and 23 are both Gaussian primes, 161 is a Blum integer.

161 is a palindromic number [2]

In the military[edit]

In music[edit]

In transportation[edit]

In other fields[edit]

161 is also:

See also[edit]

External links[edit]

References[edit]

  1. ^ "Sloane's A002412 : Hexagonal pyramidal numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-28. 
  2. ^ https://oeis.org/A002113
  3. ^ "161>88" (Documentary). Czech Republic: Antifascist Action. 2012. Retrieved 2 January 2018.