Properties of the Number 28071

Twenty-Eight Thousand Seventy-One

Basics

Value: 28070 → 28071 → 28072

Parity: odd

Prime: No

Previous Prime: 28069

Next Prime: 28081

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 3119

Divisors: 1, 3, 9, 3119, 9357, 28071

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 110110110100111

Octal: 66647

Duodecimal: 142B3

Hexadecimal: 6da7

Square: 787981041

Square Root: 167.54402406531844

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

Let f(k) = exp(π*sqrt(k)); sequence gives numbers k such that ceiling(f(k)) - f(k) < 1/10³. A127022

Integers of the form 8k+7 that can be written as a sum of four distinct squares of the form m, m+2, m+4, m+5, where m == 1 (mod 4). A243579

Expansion of (-1+3·x)/(5·x² + 1 - 2·x). A116484

Numerator of imaginary part of (3·i - 1)^-n. A124871

a(n) = A118443(n)/(n+1), where A118443 is the row sums of triangle A118441. A118444

Expansion of g.f.: (1+3·x²)/((1-x)*(1+x+2·x²)*(1-x+2·x²)). A107443

a(n) = 58·n² - 1. A158668

Numbers k such that σ(k-3) + σ(k+3) = σ(2·k). A67129

Expansion of (1-x) / (1+x²+2·x³). A78033

a(n) = 2·a(n-1) - 5·a(n-2), with a(1) = -1, a(2) = -7. A138749