Properties of the Number 81397

Eighty-One Thousand Three Hundred Ninety-Seven

Basics

Value: 81396 → 81397 → 81398

Parity: odd

Prime: No

Previous Prime: 81373

Next Prime: 81401

Digit Sum: 28

Digital Root: 1

Palindrome: No

Factorization: 23 × 3539

Divisors: 1, 23, 3539, 81397

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011110111110101

Octal: 236765

Duodecimal: 3B131

Hexadecimal: 13df5

Square: 6625471609

Square Root: 285.30159480802064

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 nondecreasing Dyck paths of semilength n and having no peaks at even level (n>=0). A nondecreasing Dyck path is a Dyck path for which the sequence of the altitudes of the valleys is nondecreasing. A121485

G.f. satisfies: A(x) = G(x·A(x)) where G(x) = -1+x + A(x) + 1/A(x). A237645

Numbers whose base-5 representation has exactly 8 runs. A43608

Number of n X 2 0..3 arrays with rows, antidiagonals and columns unimodal. A223756

a(n) = least k such that GCD of σ(k) = A000203(k) and φ(k) = A000010(k) equals n-th primorial = A002110(n). A81397