Properties of the Number 20788

Twenty Thousand Seven Hundred Eighty-Eight

Basics

Value: 20787 → 20788 → 20789

Parity: even

Prime: No

Previous Prime: 20773

Next Prime: 20789

Digit Sum: 25

Digital Root: 7

Palindrome: No

Factorization: 2 ² × 5197

Divisors: 1, 2, 4, 5197, 10394, 20788

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000100110100

Octal: 50464

Duodecimal: 10044

Hexadecimal: 5134

Square: 432140944

Square Root: 144.18044250174847

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

Numbers k such that A003415(k) == A276085(k) (mod 2310), where A003415 is the arithmetic derivative and A276085 is the primorial base log-function. A391864

Irregular table read by rows: T(n,k) is the number of k-gons, k>=3, among all distinct circles that can be constructed from the 4 vertices and the equally spaced 4·n points placed on the sides of a square, using only a compass. A372980

Number of binary "privileged words" of length n. A231208

Numbers missing from A001033 despite satisfying the necessary congruence conditions (see comments). A274470

Expansion of (1/x) * Series_Reversion( x * (1-3·x)³ / (1-2·x) ). A371363

E.g.f. satisfies A(x) = 1/(2 - exp(x·A(x)²))². A377425

a(n) = 25·n²/2 - 11·n/2 + 1. A383465

Number of 2 X 2 nonsingular 0..n matrices with rows and columns in increasing order. A183762

Number of n element 1..n arrays with each element the minimum of 6 adjacent elements of a permutation of 1..n+5 of n+5 elements. A217889

T(n,k) is the number of n element 1..n arrays with each element the minimum of k adjacent elements of a permutation of 1..n+k-1 of n+k-1 elements. A217891