This nBAB about the number

`was BAB#`

161`for the fall 2009 semester.`

161MathBabbler Number Analyst (MBNA) output: ========================================= 161 is a natural, whole, integer 161 is odd 161 proper divisors are: 1,7,23, 161 is deficient (sum of divisors is 31) 161 is unhappy 161 is not a Harshad number 161 is not prime 161 has the prime factors: 7*23 (sum=30) 161 is semiprime (biprime or 2-almost prime) 161 sum of prime factors is: 30 161 is undulating 161 is palindromic 161 is the sum of 5 consecutive primes 23 + 29 + 31 + 37 + 41 161 in octal is 0241 161 in hexadecimal is 0xa1 161 in binary is 10100001 (is odious) 161 nearest square numbers: -17...8 (144...169 [13]) sqrt(161) = 12.6886 ln(161) = 5.0814 log(161) = 2.20683 161 reciprocal is .00621118012422360248447204968944 161! is 7.59071e+286 161 is 51.2479 Pi years 161 is 8 score and 1 year 161 written as a Roman numeral is CLXI

`[NumDic.com]`

`is the difference of two squares (15^2 - 8^2 and 81^2 - 80^2).`

161

**Creator:** Gerald Thurman
[gthurman@gmail.com]

**Created:** 07 December 2009

This work is licensed under a Creative Commons Attribution 3.0 United States License.