Properties of the Number 81817

Eighty-One Thousand Eight Hundred Seventeen

Basics

Value: 81816 → 81817 → 81818

Parity: odd

Prime: Yes

Previous Prime: 81799

Next Prime: 81839

Digit Sum: 25

Digital Root: 7

Palindrome: No

Factorization: 81817

Divisors: 1, 81817

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011111110011001

Octal: 237631

Duodecimal: 3B421

Hexadecimal: 13f99

Square: 6694021489

Square Root: 286.0367109306076

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

Let A(0) = 1, B(0) = 0 and C(0) = 0. Let A(n+1) = - ∑_{k = 0..n} binomial(n,k)*C(k), B(n+1) = ∑_{k = 0..n} binomial(n,k)*A(k) and C(n+1) = ∑_{k = 0..n} binomial(n,k)*B(k). This entry gives the sequence B(n). A143631

Numbers k such that k*(k+3) gives the concatenation of two numbers m and m-2. A116274

Number of partitions p of n such that (number of even numbers in p) <= 2*(number of odd numbers in p). A241642

Tribonacci analog of A055502. A113823

Primes formed by concatenating k, k, and 7. A210513

Primes whose consecutive digits differ by 6 or 7. A48418

Primes p such that (p reversed) +6 is a square. A167472

Electron mass energy equivalent in MeV. A81817