Properties of the Number 18440

Eighteen Thousand Four Hundred Forty

Basics

Value: 18439 → 18440 → 18441

Parity: even

Prime: No

Previous Prime: 18439

Next Prime: 18443

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 2 ³ × 5 × 461

Divisors: 1, 2, 4, 5, 8, 10, 20, 40, 461, 922

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100100000001000

Octal: 44010

Duodecimal: A808

Hexadecimal: 4808

Square: 340033600

Square Root: 135.79396157414365

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

T(n,k)=Number of nXk 0..2 arrays with no element equal to any value at offset (0,-2) (-1,-2) or (-2,-1) and new values introduced in order 0..2. A275090

Maximal number of 1432 patterns in a permutation of 1,2,...,n. A100354

Number of subsets of {1..n} containing n such that every subset has a different sum. A325866

Number of staircase polygons of perimeter 2n with one (staircase polygon) hole on square lattice (not allowing rotations). A57410

T(n,k)=Number of nXk 0..3 arrays with the counts of all possible adjacent horizontal and vertical pair sum values being within one of each other. A203252

Numerators of continued fraction convergents to sqrt(549). A42050

Expansion of x²*(1-x)*(x²+x+1)*(x⁶+x³+1)/((2·x-1)*(2·x⁹-x⁶+x³-1)). A111662

Number of 2 X 2 matrices having all terms in {-n,...,0,...,n} and determinant n+1. A211142

Volatile sequence: a(n) = A018227(n)-6. A271998

G.f.: Limit_K->oo ∑_n=-oo..+oo x^n-K * (1 - xⁿ + n*(n+1)/6·x^n+K)ⁿ. A292177