Properties of the Number 21663

Twenty-One Thousand Six Hundred Sixty-Three

Basics

Value: 21662 → 21663 → 21664

Parity: odd

Prime: No

Previous Prime: 21661

Next Prime: 21673

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 29 × 83

Divisors: 1, 3, 9, 29, 83, 87, 249, 261, 747, 2407

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010010011111

Octal: 52237

Duodecimal: 10653

Hexadecimal: 549f

Square: 469285569

Square Root: 147.18355886443294

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

Numbers k such that there is 1 prime between 100·k and 100·k + 99. A186393

Numbers n such that p = n² + 2, p+2 and p+6 are consecutive primes. A86380

Number of integer partitions of n with biquanimous multiplicities. A371839

Fixed points of permutations A262323 and A262255. A262367

Number of Barlow packings with group P3(bar)m1(S) that repeat after 2n layers. A11951

Number of inequivalent (ordered) solutions to n² = sum of 8 squares of integers >= 0. A65462

Denominators of r-Egyptian fraction expansion for 1/π, where r(k) = 1/(k+1). A270585

a(n) = T(n,m) + T(n,m+1) + ... + T(n,n), m=[ (n+1)/2 ], T given by A026769. A26891

Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 101-111-101 pattern in any orientation. A146433

Number of walks within N³ (the first octant of Z³) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (-1, 1, -1), (1, -1, -1), (1, 0, 1)}. A148542