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Properties of the Number 19806

Nineteen Thousand Eight Hundred Six

Basics

Value: 19805 → 19806 → 19807

Parity: even

Prime: No

Previous Prime: 19801

Next Prime: 19813

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 2 × 3 × 3301

Divisors: 1, 2, 3, 6, 3301, 6602, 9903, 19806

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100110101011110

Octal: 46536

Duodecimal: B566

Hexadecimal: 4d5e

Square: 392277636

Square Root: 140.73379125142617

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

Triangle read by rows: T(n,k) is the number of permutations of [n] having k adjacent 3-cycles (0 <= k <= floor(n/3)), i.e., having k cycles of the form (i, i+1, i+2). A177250
G.f.: ∏k>=1 (1 + xk) / (1 - xk2). A280276
Number of permutations of [n] having exactly two adjacent 3-cycles. A370528
Number of subsets of 6 integers between 1 and n such that their sum is 1 modulo n. A381290
Number of (n+1) X (5+1) 0..1 arrays with each 2 X 2 subblock having clockwise pattern 0000 0011 or 0101. A259219
Minimal peaks in digital expansions of π: positions of peaks equal to 1. A105275
Number of right triangles on an (n+1) X 5 grid. A189809
Number of (n+1)X(5+1) 0..1 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction. A250580
Number of (n+1)X(6+1) 0..1 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction. A250581
Number of walks within N3 (the first octant of Z3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 0), (-1, 1, -1), (1, 0, 0), (1, 0, 1)}. A150306