Properties of the Number 81818

Eighty-One Thousand Eight Hundred Eighteen

Basics

Value: 81817 → 81818 → 81819

Parity: even

Prime: No

Previous Prime: 81817

Next Prime: 81839

Digit Sum: 26

Digital Root: 8

Palindrome: Yes

Factorization: 2 × 11 × 3719

Divisors: 1, 2, 11, 22, 3719, 7438, 40909, 81818

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10011111110011010

Octal: 237632

Duodecimal: 3B422

Hexadecimal: 13f9a

Square: 6694185124

Square Root: 286.03845895263805

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 triangulated (n+2)-gons rooted at an exterior edge. A6078

Numbers with mirror symmetry about middle. A6072

Starts of runs of 3 consecutive lazy-tribonacci-Niven numbers (A352107). A352109

Numbers k such that k * (k+1) is the concatenation of a number m with itself. A116285

Numbers k of the form a - b + c, such that k³ equals the decimal concatenation a//b//c and numbers k, b, and c have the same number of digits. A259379

Palindromic numbers which are sum of consecutive squares. A180436

Palindromic numbers which can be written as the sum of two or more consecutive squares. A216446

Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 26. A31704

Base 10 palindromes that start with 8. A43043

Numbers whose consecutive digits differ by 7. A48409