Properties of the Number 28221

Twenty-Eight Thousand Two Hundred Twenty-One

Basics

Value: 28220 → 28221 → 28222

Parity: odd

Prime: No

Previous Prime: 28219

Next Prime: 28229

Digit Sum: 15

Digital Root: 6

Palindrome: No

Factorization: 3 × 23 × 409

Divisors: 1, 3, 23, 69, 409, 1227, 9407, 28221

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 110111000111101

Octal: 67075

Duodecimal: 143B9

Hexadecimal: 6e3d

Square: 796424841

Square Root: 167.99107119129874

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

Triangle R, read by rows, such that R³ transforms column k of R³ into column k+1 of R³, so that column k of R³ equals column 0 of R^3·k+3, where R³ denotes the matrix cube of R. A113389

G.f.: ∏_k>=1 (1+x^k)^2·k-1. A255835

Triangle T(n,k) = 4·binomial(n,k)² - 3, read by rows, 0<=k<=n. A141596

Strong pseudoprimes to base 68. A20294

a(n) = (2·n+1)*(12·n+1). A33576

Number of length n+1 0..2 arrays with the sum of the minimum of each adjacent pair multiplied by some arrangement of +-1 equal to zero. A250413

Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 483", based on the 5-celled von Neumann neighborhood. A267829

Odd primitive abundant numbers. A6038

T(n,k)=Number of length n+1 0..k arrays with the sum of the minimum of each adjacent pair multiplied by some arrangement of +-1 equal to zero. A250419

a(n) = (a(n-1) + n)/2^k where 2^k is the largest power of 2 dividing a(n-1) + n, for n>1 with a(1)=1. A208884