Properties of the Number 81216

Eighty-One Thousand Two Hundred Sixteen

Basics

Value: 81215 → 81216 → 81217

Parity: even

Prime: No

Previous Prime: 81203

Next Prime: 81223

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 2 ⁶ × 3 ³ × 47

Divisors: 1, 2, 3, 4, 6, 8, 9, 12, 16, 18

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 10011110101000000

Octal: 236500

Duodecimal: 3B000

Hexadecimal: 13d40

Square: 6596038656

Square Root: 284.98421008891

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

Positive numbers n such that n is a multiple of (product of digits of n) * (sum of digits of n). A49102

The greedy sequence of real numbers at least 1 that do not contain any 3-term geometric progressions with integer ratio. A235054

Records in A007374. A105207

Numbers with prime factorization pq^3r^6. A190467

a(n) is the number of 5 element sets of distinct integer-sided trapezoids whose base angles are 60 degrees that fill an equilateral triangular grid of side n units formed by directly binary space partitioning 3-trapezoid sets without forming 4-trapezoid sets. A391203

Numbers k such that k divided by ((sum of digits of k) multiplied by (product of digits of k)) is prime. A66042

a(n) = (nⁿ-(-1)ⁿ)/(n+1). A81216

Table read by antidiagonals: T(h,n) is the number of n-step self avoiding walks on a 3D cubic lattice confined inside a box of size 2h X 2h X 2h where the walk starts at the center of the box. A337023

G.f.: A(x) = 1 + ∑_n>=1 xⁿ*A(x)^3ⁿ. A195260