Properties of the Number 90021

Ninety Thousand Twenty-One

Basics

Value: 90020 → 90021 → 90022

Parity: odd

Prime: No

Previous Prime: 90019

Next Prime: 90023

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 3 × 37 × 811

Divisors: 1, 3, 37, 111, 811, 2433, 30007, 90021

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10101111110100101

Octal: 257645

Duodecimal: 44119

Hexadecimal: 15fa5

Square: 8103780441

Square Root: 300.03499795857147

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

Coefficient of x⁴ in expansion of (1+x+x²)ⁿ. A5712

a(n) = ceiling(A107293(n)/2). A173693

Number of zero-sum -n..n arrays of 6 elements with first and second differences also in -n..n. A201877

a(n) = Trinomial(2·n+1, 4) = (1/6)*n*(2·n + 1)*(2·n² + 9·n + 1), n >= 0. A302709

a(n-5) is the number of nonempty subsets of {1,2,...,n} such that the difference of successive elements is at least 5. A330910

a(n) = floor( exp(γ) k log log k ) - σ(k), where γ is Euler's constant (A001620) and σ(k) is sum of divisors of k (A000203), the n-th colossally abundant number (A004490). A279702

Fibonacci numbers: F(n) = F(n-1) + F(n-2) with F(0) = 0 and F(1) = 1. A45

a(n) = 4·a(n-1) - a(n-2) with a(0) = 0, a(1) = 1. A1353

a(n) = n·3^n-4. A6234

Square array read by antidiagonals: T(m,n) = number of spanning trees in an m X n grid. A116469