### About the Number 520 (five hundred twenty)

520 was the smallest number without a nBAB on 26 June 2018.

```MathBabbler Number Analyst (MBNA) output:
=========================================
520 is natural, counting, whole, integer
520 is even (not odd)
520 proper divisors are: 1,2,4,5,8,10,13,20,26,40,52,65,104,130,260,
520 has 15 proper divisors
520 is abundant (sum of divisors is 740; ratio: 1.42308)
520 is unhappy
520 is not a Squarefree Number: 4,
520 is composite (not prime)
520 has the prime factors: 2*2*2*5*13 (sum=24)
520 is a 13-smooth number
520 is untouchable
520 is sum of two squares
...520 = 14^2 + 18^2
...520 = 6^2 + 22^2
520 is Recaman number 1221
520 is *not* arithmetic (A003601)
520 is the sum of 2 consecutive primes
520 = 257 + 263
520 digital root is 7
520 in octal is 01010
520 in binary is 1000001000 (is evil)
520 nearest square numbers: -36...9 (484...529 [23])
sqrt(520) = 22.8035
ln(520) = 6.25383
log(520) = 2.716
520! is 1.76104e+1188
520 is 165.521 Pi years
520 is 26 scoreyears
520 written as a Roman numeral is DXX
520 is 131^2 - 129^2 and 2 * (131 + 129)
520 is a multiple of 2 & it contains a 2 (A121022)
520 is a multiple of 5 & it contains a 5 (A121025)
520 is a multiple of 20 & it contains a 20 (A121040)
520 is a multiple of 52 & it contains a 52
______
520 reciprocal is 0.001923076
remainders:
1,10,100,480,120,160,40,400,360,480
```

Creator: Gerald Thurman [gthurman@gmail.com]
Created: 26 June 2018