About the Number 209 (two hundred nine)

The OEIS A117746 (n^2 - n - 1 and an alternate) nBAB collection was created on 21 February 2014. Note: The number 8371 was responsible for its creation. The MBNA was modified to check for numbers in the OEIS A117746 sequence and on 2 March 2014 the number 209 was the smallest number in the sequence that didn't have a nBAB.

MathBabbler Number Analyst (MBNA) output:
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209 is a natural, whole, integer
209 is odd
209 proper divisors are: 1,11,19,
209 has 3 proper divisors
209 is deficient (sum of divisors is 31; ratio: 0.148325)
209 is unhappy
209 is a Squarefree Number
209 is Harshad (Niven) number
209 is composite (not prime)
209 has the prime factors: 11*19 (sum=30)
209 is semiprime (biprime or 2-almost prime)
209 is in OEIS::A117746
209 in octal is 0321
209 in hexadecimal is 0xd1
209 in binary is 11010001 (is evil)
209 nearest square numbers: -13...16 (196...225 [15])
sqrt(209) = 14.4568
ln(209) = 5.34233
log(209) = 2.32015
209 reciprocal is .00478468899521531100478468899521
209 is 66.5268 Pi years
209 is 10 score and 9 years
209 written as a Roman numeral is CCIX
209 is 105^2 - 104^2 and 105 + 104 = 209

The following was in the Wikipedia entry for the number 209.

   209 = 1^6 + 2^5 + 3^4 + 4^3 + 5^2 + 6^1

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 02 March 2014

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