Properties of the Number -20880

Twenty Thousand Eight Hundred Eighty

Basics

Value: -20881 → -20880 → -20879

Parity: even

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 2 ⁴ × 3 ² × 5 × 29

Divisors: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: -101000110010000

Octal: -50620

Duodecimal: -10100

Hexadecimal: -5190

Square: 435974400

Square Root: 144.49913494550754

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

G.f. A(x) satisfies A(x) = 1 + x * ((1 - x) / A(x))³. A366436

E.g.f.: ∏_k>=1 (1 - x^k/k). A292359

Jabotinsky-triangle related to A039647. A39692

a(n) = n²*(n²+1). A71253

Numbers k such that σ (x) = k has exactly 12 solutions. A60676

T(n,k) = Number of n X k 0..2 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. A279657

Coefficients in expansion of Eisenstein series -q·E'_2. A76835

a(n) = (1/n) * ∑_d∣n moebius(n/d) * Lucas(d)², where Lucas(n) = A000204(n). A203853

"CHK" (necklace, identity, unlabeled) transform of 1, 2, 3, 4, ... A32170

Sums of distinct powers of 12. A33048