### Properties of the number 9912:

9912 = 2^{3}× 3 × 7 × 59 is the 8689

^{th}composite number and is not squarefree.

9912 has 4 distinct prime factors, 32 divisors, 19 antidivisors and 2784 totatives.

9912 has a semiprime digit sum 21 in base 10.

9912 has a Fibonacci digit sum 21 in base 10.

9912 has a triangular digit sum 21 in base 10.

Reversing the decimal digits of 9912 results in a semiprime.

9912 = 2479

^{2}- 2477

^{2}= 1241

^{2}- 1237

^{2}= 829

^{2}- 823

^{2}= 419

^{2}- 407

^{2}= 361

^{2}- 347

^{2}= 191

^{2}- 163

^{2}= 139

^{2}- 97

^{2}= 101

^{2}- 17

^{2}is the difference of 2 nonnegative squares in 8 ways.

9912 is the difference of 2 positive pentagonal numbers in 3 ways.

9912 = 20

^{2}+ 26

^{2}+ 94

^{2}is the sum of 3 positive squares.

9912

^{2}is the sum of 3 positive squares.

9912 is a divisor of 827

^{2}- 1.

9912 = '991' + '2' is the concatenation of 2 prime numbers.

9912 is palindromic in (at least) base 39.

9912 in base 38 = 6WW and consists of only the digits '6' and 'W'.

9912 in base 39 = 6K6 and consists of only the digits '6' and 'K'.

9912 in base 44 = 55C and consists of only the digits '5' and 'C'.

### The number 9912 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.A002597: Number of partitions into one kind of 1's, two kinds of 2's, and three kinds of 3's.

A006967: Number of graceful permutations of length n.

A025231: a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-1)*a(1) for n >= 3.

A047891: Number of planar rooted trees with n nodes and tricolored end nodes.

A049374: A triangle of numbers related to triangle A030527.

A092000: Numbers that can be expressed as the difference of the squares of primes in exactly four distinct ways.

A105720: Triangular matchstick numbers in the class of prime numbers: sum of n-th and next n primes.

A180281: Triangle read by rows: T(n,k) = number of arrangements of n indistinguishable balls in n boxes with the maximum number of balls in any box equal to k.

A235047: Permutation of nonnegative integers: a(n) = A235199(A234840(n+1)-1).

A241648: Numbers m such that the GCD of the x's that satisfy sigma(x)=m is 3.

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