About the Number 381 (three hundred eighty-one)

381 was the smallest number that didn't have a nBAB on 2 January 2017. The next smallest number without a nBAB is 382. Note: 382 to 398, inclusive, did not have nBABs when this nBAB was created.

MathBabbler Number Analyst (MBNA) output:
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381 is natural, counting, whole, integer
381 is odd (not even)
381 is not extremely odd
381 proper divisors are: 1,3,127,
381 has 3 proper divisors
381 is deficient (sum of divisors is 131; ratio: 0.343832)
381 is unhappy
381 is a Squarefree Number
381 is composite (not prime)
381 has the prime factors: 3*127 (sum=130)
381 is semiprime (biprime or 2-almost prime)
381 is a 127-smooth number
381 is Arithmetic (A003601)
381 is the sum of 16 consecutive primes
381 = 2 + 3 + 5 + 7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 + 41 + 43 + 47 + 53
381 in octal is 0575
381 in hexadecimal is 0x17d
381 in binary is 101111101 (is odious)(is palindromic)
381 nearest square numbers: -20...19 (361...400 [20])
sqrt(381) = 19.5192
ln(381) = 5.9428
log(381) = 2.58092
381! is 3.59638e+819
381 is 121.276 Pi years
381 is 19 score and 1 year
381 written as a Roman numeral is CCCLXXXI
381 is 191^2 - 190^2 and 191 + 190 = 381
381 is a multiple of 1 & it contains a 1 (A011531)
381 is a multiple of 3 & it contains a 3 (A121023)
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381 reciprocal is 0.002624671916010498687664041994750656167979
remainders: 
1,10,100,238,94,178,256,274,73,349,61,229,4,40,19,190,376,331,262,334,292,253,244,154,16,160,76,379,361,181,286,193,25,250,214,235,64,259,304,373,301,343,1

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 02 January 2017

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