Properties of the Number 71688

Seventy-One Thousand Six Hundred Eighty-Eight

Basics

Value: 71687 → 71688 → 71689

Parity: even

Prime: No

Previous Prime: 71671

Next Prime: 71693

Digit Sum: 30

Digital Root: 3

Palindrome: No

Factorization: 2 ³ × 3 × 29 × 103

Divisors: 1, 2, 3, 4, 6, 8, 12, 24, 29, 58

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10001100000001000

Octal: 214010

Duodecimal: 355A0

Hexadecimal: 11808

Square: 5139169344

Square Root: 267.74614843168143

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

Coefficient of xⁿ in (1 - (n-1)*x - n·x²)ⁿ. A307885

G.f. A(x) satisfies: 1 = ...(((((A(x) - x)^1/2 - x²)^1/2 - x³)^1/2 - x⁴)^1/2 - x⁵)^1/2 -...- xⁿ)^1/2 -..., an infinite series of nested square roots. A274965

Nonnegative values·of solutions (x, y) to the Diophantine equation x²+(x+103)² = y². A157119

Irreducible polynomial coefficient of singular value associated with sqrt(2n). A78878

a(n) = ∑_k=0..2n-1 T(n,k) * T(n,k+1), with T given by A027113. A27141

Number of ways to build a contiguous building with n LEGO blocks of size 1 X 2 on top of a fixed block of the same size so that the building is flat, i.e., with all blocks in parallel position and symmetric after a rotation by 180 degrees. A123769

Number of plane trees with even number of leaves. A71688

Self-convolution square root of the odd bisection of A274965. A275752

Array read by antidiagonals upwards: A(n, k) = if(n mod 2 = 0, floor((n+2^k-2) / 2^k), n * (k·2^k+1) + 1). A391114