Properties of the Number 18708

Eighteen Thousand Seven Hundred Eight

Basics

Value: 18707 → 18708 → 18709

Parity: even

Prime: No

Previous Prime: 18701

Next Prime: 18713

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 2 ² × 3 × 1559

Divisors: 1, 2, 3, 4, 6, 12, 1559, 3118, 4677, 6236

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100100100010100

Octal: 44424

Duodecimal: A9B0

Hexadecimal: 4914

Square: 349989264

Square Root: 136.77719108096935

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 binary arrays with top left element equal to 1 and no two ones adjacent horizontally or nw-se. A228796

T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime. A251845

T(n,k)=Number of nXk binary matrices with no initial bit string in any row or column divisible by 6. A181039

Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where T(n,k) = ∑_j=0..n 2^j * binomial(n,j) * binomial(k·n+j+1,n)/(k·n+j+1). A336574

a(n) = ∑_k=0..n 2^k * binomial(n,k) * binomial(n²+k+1,n)/(n²+k+1). A336577

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

G.f. A(x) satisfies A(x) = 1 + x·A(x)⁴ * (1 + 2·A(x)). A336572

a(n) = 2·a(n-1) + 2·a(n-2) + 2·a(n-3) - a(n-4) with a(0)=0, a(1)=1, a(2)=4, a(3)=11. A387018

a(n) = ∑_i=1..n LookAndSay(i). A79664

Index of first occurrence of n in A165633. A165765