Properties of the Number 6421

Six Thousand Four Hundred Twenty-One

Basics

Value: 6420 → 6421 → 6422

Parity: odd

Prime: Yes

Previous Prime: 6397

Next Prime: 6427

Digit Sum: 13

Digital Root: 4

Palindrome: No

Factorization: 6421

Divisors: 1, 6421

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1100100010101

Octal: 14425

Duodecimal: 3871

Hexadecimal: 1915

Square: 41229241

Square Root: 80.1311425102625

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(1) = 2; a(n) is smallest prime > 2·a(n-1). A55496

Numbers which converge to 2592 under repeated application of the powertrain map of A133500. A135384

First differences of A080735. A163963

E.g.f.: 1/(1 + LambertW(1-exp(x))), where LambertW() is the Lambert W-function. A282190

A list of equal temperaments (equal divisions of the octave) whose nearest scale steps are closer and closer approximations to the ratios of 8 musical tones: 8/7 16/11 5/4 4/3 3/2 8/5 11/8 7/4. A60527

Number of integer compositions of n whose leaders of anti-runs are strictly decreasing. A374680

Primes with distinct digits in descending order. A52014

Father primes of order 9. A136078

a(n) is the smallest prime q such that (q-p)/(r-q) = n, where p<q<r are consecutive primes (or 0 if none exist). A179256

Bases b where exactly six primes p with p < b exist such that p is a base-b Wieferich prime. A325882