Properties of the Number -1684

Six Hundred Eighty-Four

Basics

Value: -1685 → -1684 → -1683

Parity: even

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 ² × 421

Divisors: 1, 2, 4, 421, 842, 1684

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -11010010100

Octal: -3224

Duodecimal: -B84

Hexadecimal: -694

Square: 2835856

Square Root: 41.036569057366385

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

Expansion of ∏_k>=1 (1 - x^k/(1 - x)). A307599

Determinant of n X n matrix containing the first n² composites in increasing order. A321685

First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 131", based on the 5-celled von Neumann neighborhood. A270224

Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where column k is the expansion of B(x)^k, where B(x) is the g.f. of A384941. A384944

Expansion of sinh(sin(x)*x)/2. A24238

Centered triangular numbers: a(n) = 3·n*(n-1)/2 + 1. A5448

Number of points on surface of tetrahedron; coordination sequence for sodalite net (equals 2·n²+2 for n > 0). A5893

a(1)=a(2)=a(3)=1, a(4)=3; thereafter a(n) = a(n-1) + a(n-3). A179070

Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n and height k (1 <= k <= n). A80936

a(n) = n² + 3. A117950