Properties of the Number 68605

Sixty-Eight Thousand Six Hundred Five

Basics

Value: 68604 → 68605 → 68606

Parity: odd

Prime: No

Previous Prime: 68597

Next Prime: 68611

Digit Sum: 25

Digital Root: 7

Palindrome: No

Factorization: 5 × 13721

Divisors: 1, 5, 13721, 68605

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10000101111111101

Octal: 205775

Duodecimal: 33851

Hexadecimal: 10bfd

Square: 4706646025

Square Root: 261.92556194461054

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

a(0) = 16, after which, if (2·a(n-1)) - 1 = ∏_{k >= 1} (p_k)^c_k then a(n) = ∏_{k >= 1} (p_k-1)^c_k, where p_k indicates the k-th prime, A000040(k). A246345

Decimal expansion of the constant E₃(2) := sum {k = 0.. inf} (-1)^floor(k/3)*k²/k! = 1/1! + 2²/2! - 3²/3! - 4²/4! - 5²/5! + + + - - - ... = 0.68605 60507 ... . A143627

Let A(x) satisfy: A(x) = 1 + x·A(x)^φ² where φ = (sqrt(5)+1)/2, then this sequence equals the integer part of the coefficients of A(x). A184786

Reverse binary expansion of the Fibonacci numbers. A143250

Number of functions from [1,2,...,n] to [1,2,...,n] such that the image contains exactly two elements. A68605