Properties of the Number 39840

Thirty-Nine Thousand Eight Hundred Forty

Basics

Value: 39839 → 39840 → 39841

Parity: even

Prime: No

Previous Prime: 39839

Next Prime: 39841

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 2 ⁵ × 3 × 5 × 83

Divisors: 1, 2, 3, 4, 5, 6, 8, 10, 12, 15

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1001101110100000

Octal: 115640

Duodecimal: 1B080

Hexadecimal: 9ba0

Square: 1587225600

Square Root: 199.5995991979944

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

Triangle T(n,k) read by rows: T(n,k) = number of cycles of length 2k in the binary n-cube, for n >= 2, k = 2, 3, ..., 2^n-1. A85452

Number of different strings of length n+4 obtained from "123...n" by iteratively duplicating any substring. A137741

Numbers·such that there exist three integers 0<x<=y, z>0 and w>0 such that σ(x)³ = σ(y)³ = x³ + y³ + z³ + w³. A385397

Braided power sequence: this is b(n+1) = 3·b(n) + 2·d(n) - c(n), A065693 is c(n+1) = 3·c(n) + 2·b(n) - d(n) and A065694 is d(n+1) = 3·d(n) + 2·c(n) - b(n), starting with b(0) = 0, c(0) = 1 and d(0) = 2. A65692

Group successively larger composite numbers so that the sum of the n-th group is a multiple of n. Sequence gives the sum of the terms in the n-th group. A74120

θ series of lattice A₂ tensor D₅ (dimension 10, det. 3888, min. norm 4). A33697

Number of 8-cycles in the hypercube graph Q_n. A364688

Triangle T(n,k) for A(x)^k=sum(n>=k T(n,k)*xⁿ), where o.g.f. A(x) satisfies A(x)=(a+b·x*A(x))/(c-d·x*A(x)), a=1,b=2,c=1,d=2. A183875

Number of partitions satisfying cn(0,5) <= cn(2,5) + cn(3,5). A39840