Properties of the Number 66805

Sixty-Six Thousand Eight Hundred Five

Basics

Value: 66804 → 66805 → 66806

Parity: odd

Prime: No

Previous Prime: 66797

Next Prime: 66809

Digit Sum: 25

Digital Root: 7

Palindrome: No

Factorization: 5 × 31 × 431

Divisors: 1, 5, 31, 155, 431, 2155, 13361, 66805

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10000010011110101

Octal: 202365

Duodecimal: 327B1

Hexadecimal: 104f5

Square: 4462908025

Square Root: 258.46663227581234

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 n X 2 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 3 binary array having nonzero determinant, with rows and columns of the latter in lexicographically nondecreasing order. A227554

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), (0, 0, 1), (0, 1, -1), (1, 0, -1)}. A148562

Number of length n left factors of Dyck paths having no base pyramids. A191789

a(n) is the least k such that n + ∑_i=1..k A018252(i) is prime; or 0 if none exists. A66805