Properties of the Number 806

Eight Hundred Six

Basics

Value: 805 → 806 → 807

Parity: even

Prime: No

Previous Prime: 797

Next Prime: 809

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 2 × 13 × 31

Divisors: 1, 2, 13, 26, 31, 62, 403, 806

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 1100100110

Octal: 1446

Duodecimal: 572

Hexadecimal: 326

Square: 649636

Square Root: 28.39013913315678

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

Sum of totient function: a(n) = ∑_k=1..n φ(k), cf. A000010. A2088

Number of weakly ordered plane trees with n leaves. A196545

Number of sublattices of index n in generic 3-dimensional lattice. A1001

Generalized 11-gonal (or hendecagonal) numbers: m*(9·m - 7)/2 with m = 0, 1, -1, 2, -2, 3, -3, ... A195160

Numbers that are the sum of 12 positive 5th powers. A3357

a(n) = n*(n+5). A28557

Numbers n such that n¹⁰ + n⁹ + n⁸ + n⁷ + n⁶ + n⁵ + n⁴ + n³ + n² + n + 1 is prime. A162862

A triangle formed like Pascal's triangle, but with n² on the left border and 2ⁿ on the right border instead of 1. A228196

Number of pairwise coprime strict compositions of n, where a singleton is not considered coprime unless it is (1). A337561

Palindromic in base 5. A29952