Properties of the Number 21554

Twenty-One Thousand Five Hundred Fifty-Four

Basics

Value: 21553 → 21554 → 21555

Parity: even

Prime: No

Previous Prime: 21529

Next Prime: 21557

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 2 × 13 × 829

Divisors: 1, 2, 13, 26, 829, 1658, 10777, 21554

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010000110010

Octal: 52062

Duodecimal: 10582

Hexadecimal: 5432

Square: 464574916

Square Root: 146.81280598094978

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

Third differences of Catalan numbers A000108. A33434

Number of compositions (ordered partitions) of n into an odd number of triangular numbers. A339417

p-INVERT of the positive integers, where p(S) = (1 - S)(1 - S²). A290929

Number of binary strings of length n with equal numbers of 0001 and 1110 substrings. A164165

Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 12. A31600

Coordination sequence for B₁₃ lattice. A107546

Number of ways to write n as an ordered sum of 1s, 2s, 3s and 4s such that no 2 precedes any 1 and no 3 precedes any 1 or 2. A123569

G.f.: (1+x+x²+x³)/(1-x²-2·x³-x⁴+x⁶). A234273

Decimal expansion of 1/550. A21554