Properties of the Number 1866

One Thousand Eight Hundred Sixty-Six

Basics

Value: 1865 → 1866 → 1867

Parity: even

Prime: No

Previous Prime: 1861

Next Prime: 1867

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 2 × 3 × 311

Divisors: 1, 2, 3, 6, 311, 622, 933, 1866

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 11101001010

Octal: 3512

Duodecimal: 10B6

Hexadecimal: 74a

Square: 3481956

Square Root: 43.197222132910355

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 ways of placing n labeled balls into n unlabeled (but 3-colored) boxes. A27710

Triangle G(n,k) read by rows, for 0 <= k <= n, where G(n, 0) = G(n+1, n+1) = 1, G(n+2, n+1) = 2, G(n+3, n+1) = 4, and G(n+4, m) = G(n+1, m-1) + G(n+1, m) + G(n+2, m) + G(n+3, m) for n >= 0 and m = 1..n+1. A140997

Number of 4's in the last section of the set of partitions of n. A182714

Coefficients in expansion of ∑_{n >= 1} xⁿ/(1-xⁿ)⁴. A59358

Number of plane partitions of n with at most two rows. A990

a(n) is the number of completed steps before being trapped for a knight moving on a square-spiral numbered board where the knight moves to an unvisited square with the lowest spiral number and with n or fewer visited neighbors. It only moves to squares with n+1 or more visited neighbors when no other squares are available, and if two or more such squares are present it chooses the square with the fewest visited neighbors, then the square with the lowest spiral number if still tied. A329520

Numbers k in pairs (j,k), with j <> k +- 1, such that the sum of their cubes is equal to a centered cube number. A352136

List of different composites in Pascal-like triangles with index of asymmetry y = 2 and index of obliquity z = 0 or z = 1. A141066

Number of strict integer partitions of n with a unique prime part. A379305

Cube of lower triangular matrix of A056857 (successive equalities in set partitions of n). A78938