Properties of the Number 66721

Sixty-Six Thousand Seven Hundred Twenty-One

Basics

Value: 66720 → 66721 → 66722

Parity: odd

Prime: Yes

Previous Prime: 66713

Next Prime: 66733

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 66721

Divisors: 1, 66721

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 10000010010100001

Octal: 202241

Duodecimal: 32741

Hexadecimal: 104a1

Square: 4451691841

Square Root: 258.30408436569485

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-dimensional partitions of n up to conjugacy. A119266

Primes p of Erdos-Selfridge class 5+ with largest prime factor of p+1 not of class 4+. A129473

a(n) = a(n-2) - (n-1)*a(n-3), with a(0) = 0, a(1) = 1, a(2) = 2. A122021

Primes p such that (p¹²⁸ + 1)/2 is prime. A341230

Number of ways to fill a Young diagram with positive integers summing to n such that the rows are weakly decreasing and the columns are weakly increasing. A323580

Right diagonal of triangle in A072467. A72469

Primes which contain the fax number of the beast (667). A321001

Nonprimes in A066720. A66721