Properties of the Number 66885

Sixty-Six Thousand Eight Hundred Eighty-Five

Basics

Value: 66884 → 66885 → 66886

Parity: odd

Prime: No

Previous Prime: 66883

Next Prime: 66889

Digit Sum: 33

Digital Root: 6

Palindrome: No

Factorization: 3 × 5 × 7 ³ × 13

Divisors: 1, 3, 5, 7, 13, 15, 21, 35, 39, 49

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 10000010101000101

Octal: 202505

Duodecimal: 32859

Hexadecimal: 10545

Square: 4473603225

Square Root: 258.62134482675634

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

Odd numbers k for which A003961(k) > 2·k and A003961(k)-2·k OR A003961(k)-σ(k) = A003961(k)-2·k, where OR is bitwise-or (A003986) and A003961 is fully multiplicative with a(p) = nextprime(p). A388029

Indices of primes in sequence defined by A(0) = 91, A(m) = 10·A(m-1) - 9 for m > 0. A100997

Numbers for which the number of prime divisors counted with multiplicity and the sum of the distinct prime divisors are both perfect. A233563

Let f(x) = 1 + ∑_j>=4 (|μ(j)| - |μ(j-1)|)*x^j, where μ(n) is the Möbius function (A008683). Then a(n) is n times the coefficient of xⁿ in the expansion of log(f(x)). A262400

Number of (undirected) cycles in the n-flower graph. A368191

a(n) = (prime(n)² + 1)/2. A66885

Numbers k such that there are precisely 8 groups of orders k and k + 1. A295993