### Properties of the number 21429:

21429 = 3^{2}× 2381 is the 19023

^{th}composite number and is not squarefree.

21429 has 2 distinct prime factors, 6 divisors, 7 antidivisors and 14280 totatives.

21429 has a Fibonacci digit product 144 in base 10.

21429 = 1

^{3}+ 21

^{3}+ 23

^{3}is the sum of 3 positive cubes in 1 way.

21429 = 10715

^{2}- 10714

^{2}= 3573

^{2}- 3570

^{2}= 1195

^{2}- 1186

^{2}is the difference of 2 nonnegative squares in 3 ways.

21429 is the sum of 2 positive triangular numbers.

21429 is the difference of 2 positive pentagonal numbers in 1 way.

21429 = 102

^{2}+ 105

^{2}is the sum of 2 positive squares in 1 way.

21429 = 7

^{2}+ 8

^{2}+ 146

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

21429

^{2}= 621

^{2}+ 21420

^{2}is the sum of 2 positive squares in 1 way.

21429

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

21429 is a proper divisor of 1021

^{21}- 1.

21429 = '2' + '1429' is the concatenation of 2 prime numbers.

21429 is palindromic in (at least) the following bases: -32, and -51.

21429 in base 11 = 15111 and consists of only the digits '1' and '5'.

21429 in base 28 = r99 and consists of only the digits '9' and 'r'.

21429 in base 34 = ii9 and consists of only the digits '9' and 'i'.

21429 in base 35 = hh9 and consists of only the digits '9' and 'h'.

### The number 21429 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.A031846: Period of continued fraction for sqrt(n) contains exactly 78 ones.

A037101: Trajectory of 3 under map n->7n+1 if n odd, n->n/2 if n even

A271412: Partial sums of the number of active (ON,black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 358", based on the 5-celled von Neumann neighborhood.

A271623: a(0)=7; a(n) = 7*a(n-1) + 1 if a(n-1) is odd, a(n) = a(n-1)/2 otherwise.

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