Properties of the Number 21869

Twenty-One Thousand Eight Hundred Sixty-Nine

Basics

Value: 21868 → 21869 → 21870

Parity: odd

Prime: No

Previous Prime: 21863

Next Prime: 21871

Digit Sum: 26

Digital Root: 8

Palindrome: No

Factorization: 19 × 1151

Divisors: 1, 19, 1151, 21869

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010101101101

Octal: 52555

Duodecimal: 107A5

Hexadecimal: 556d

Square: 478253161

Square Root: 147.8817094843037

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

a(n) = 30·n² - 1. A158560

Numerator of A166100(A166101(n))/A166102(n). A166272

a(n) = 10·3ⁿ - 1. A198645

Numbers k such that A276086(k) is a multiple of A003415(k) and A276087(k) is a multiple of A327859(k). A393071

a(n) = 729·n - 1. A158395

a(n) = n³ - 3n² + 3. A177058

Array A read by upward antidiagonals in which the entry in row n and column k is defined by A(n,k) = (3/2)*(3^k - 1) + A265159(n,k), n,k >= 1. A265161

a(n) = sum of numbers without digit 1 and with product of digits = n-th 7-smooth number. A130975

The Wiener index of the graph obtained by applying Mycielski's construction to a benzenoid consisting of a linear chain of n hexagons. A228597

Numbers having four 5's in base 8. A43444