### About the Number 261 (two hundred sixty-one)

261 was the smallest number that didn't have a nBAB on 7 April 2016. MathBabbler is trying to ensure that the numbers 0-300 have nBABs by the end of the Spring 2016 Semester. With the posting of this nBAB for 261, 262 became the smallest number without a nBAB on 7 April 2016.

```MathBabbler Number Analyst (MBNA) output:
=========================================
261 is a natural, whole, integer
261 is odd
261 proper divisors are: 1,3,9,29,87,
261 has 5 proper divisors
261 is deficient (sum of divisors is 129; ratio: 0.494253)
261 is unhappy
261 is not a Squarefree Number: 9,
261 is Harshad (Niven) number
261 is composite (not prime)
261 has the prime factors: 3*3*29 (sum=35)
261 is a 29-smooth number
261 is a Moran Number
261 is a lucky number
261 is Arithmetic (A003601)
261 in octal is 0405
261 in hexadecimal is 0x105
261 in binary is 100000101 (is odious)
261 nearest square numbers: -5...28 (256...289 )
sqrt(261) = 16.1555
ln(261) = 5.56452
log(261) = 2.41664
261 reciprocal is .00383141762452107279693486590038
261! is 9.99681e+518
261 is 83.0789 Pi years
261 is 13 score and 1 year
261 written as a Roman numeral is CCLXI
261 is 131^2 - 130^2 and 131 + 130 = 261
261 is a multiple of 1 & it contains a 1 (A011531)
```

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 07 April 2016 