Properties of the Number 66605

Sixty-Six Thousand Six Hundred Five

Basics

Value: 66604 → 66605 → 66606

Parity: odd

Prime: No

Previous Prime: 66601

Next Prime: 66617

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 5 × 7 × 11 × 173

Divisors: 1, 5, 7, 11, 35, 55, 77, 173, 385, 865

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10000010000101101

Octal: 202055

Duodecimal: 32665

Hexadecimal: 1042d

Square: 4436226025

Square Root: 258.0794451326955

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

Number of 3-level labeled linear rooted trees with n leaves. A50351

E.g.f.: (8 - 7·cosh(x)) / (13 - 12·cosh(x)). A247082

Generalized Fubini numbers. Square array read by ascending antidiagonals, A(n,k) = 1 + k*(∑_j=1..n-1 C(n,j)*A(j,k)); n>=0 and k>=0. A257565

Related to Fibonacci numbers, see the Formula section. A215082

Number of 5-dimensional centered tetrahedral numbers. A8499

Numbers k such that A360327(k) = A360327(k+1) > 1. A360358

a(n) = A215082(2·n+1). A215109

Matrix product of triangle of Stirling numbers of second kind A008277 and square of unsigned Lah triangle A105278. A308440

Numbers k such that φ(k)/λ(k) increases to a record value, where φ(k) is the Euler totient function (A000010) and λ(k) is the Carmichael λ function (A002322). A66605