Properties of the Number 81689

Eighty-One Thousand Six Hundred Eighty-Nine

Basics

Value: 81688 → 81689 → 81690

Parity: odd

Prime: Yes

Previous Prime: 81677

Next Prime: 81701

Digit Sum: 32

Digital Root: 5

Palindrome: No

Factorization: 81689

Divisors: 1, 81689

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011111100011001

Octal: 237431

Duodecimal: 3B335

Hexadecimal: 13f19

Square: 6673092721

Square Root: 285.8128758471178

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 list of equal temperaments (equal divisions of the octave) whose nearest scale steps are closer and closer approximations to the ratios of six simple musical tones: 8/7 5/4 4/3 3/2 8/5 7/4. A60526

First of four consecutive primes p,q,r,s such that the sum of numerator and denominator of p/q + q/r, p/q + r/s, and q/r + r/s, are all prime. A355696

G.f. A(x) satisfies: 1/(1 + x) = A(x)*A(x²)²*A(x³)³*A(x⁴)⁴* ... *A(x^k)^k* ... A307657

A005228 - 1. A81689