Properties of the Number -18209

Eighteen Thousand Two Hundred Nine

Basics

Value: -18210 → -18209 → -18208

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 131 × 139

Divisors: 1, 131, 139, 18209

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

5184 Try Today's Challenge

Representations

Binary: -100011100100001

Octal: -43441

Duodecimal: -A655

Hexadecimal: -4721

Square: 331567681

Square Root: 134.94072772888103

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

Expansion of e.g.f. cos(tanh(tan(x))), even powers only. A9086

a(n) = prime(n)*prime(n+2). A90076

T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000101 or 00010101. A260106

Sequence of pairwise relatively prime numbers of class P₅ (see comment in A275246). A275249

Number of labeled T₀-hypergraphs with n distinct hyperedges (empty hyperedge excluded). A59089

Numbers k such that exactly three d in the range d <= k/2 exist which divide binomial(k-d-1,d-1) and which are not coprime to k. A178099

S₅ sequence in partition of integers > 1 described in A240521. A240522

Semiprimes whose prime factors are of equal binary length and which differ from each other in one bit position only. A261073

a(n) = 2·a(n-1) + 5·a(n-2), a(0) = 1, a(1) = 3. A180168

Semiprimes whose prime factors differ from each other in one bit position only. A261077