Properties of the Number 81761

Eighty-One Thousand Seven Hundred Sixty-One

Basics

Value: 81760 → 81761 → 81762

Parity: odd

Prime: Yes

Previous Prime: 81749

Next Prime: 81769

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 81761

Divisors: 1, 81761

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011111101100001

Octal: 237541

Duodecimal: 3B395

Hexadecimal: 13f61

Square: 6684861121

Square Root: 285.9388046418324

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

Partial sums of A001158: ∑_j=1..n sigma₃(j). A64603

Rectangular array, read by antidiagonals, where row e.g.f.s, R(n,x), satisfy: d/dx log( R(n,x) ) = R(n+1,x)^2ⁿ with R(n,0) = 1; that is, the logarithmic derivative of the e.g.f. of row n equals the e.g.f. of row n+1 to the 2ⁿ power, for n>=0. A159314

Primes with 12 as smallest positive primitive root. A61325

a(n)/2^n² is the coefficient of xⁿ/n! in F(x)^1/2ⁿ where F(x) is the e.g.f. of A159315. A159317

Primes p whose smallest positive primitive root (mod p) is not squarefree. A205581

Primes that can be generated by the concatenation in base 9, in ascending order, of two consecutive integers read in base 10. A287312

Least number >n having same type of prime factorization, a(1)=1. A81761

Number of Barker codes (or Barker sequences) of length n up to reversals and negations. A91704

Odd numbers n such that 3ⁿ+1 is a sum of two squares. A272069