Properties of the Number 18640

Eighteen Thousand Six Hundred Forty

Basics

Value: 18639 → 18640 → 18641

Parity: even

Prime: No

Previous Prime: 18637

Next Prime: 18661

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 ⁴ × 5 × 233

Divisors: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100100011010000

Octal: 44320

Duodecimal: A954

Hexadecimal: 48d0

Square: 347449600

Square Root: 136.5283853270081

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

a(n) = n*(7·n²-4)/3. A63521

Number of distinct integer partitions whose parts can be combined together using additions and multiplications to obtain n, with the exception that 1's can only be added and not multiplied with other parts. A319913

Number of cubes of primes <= 2ⁿ. A60969

a(n) = dot_product(1,2,...,n)*(6,7,...,n,1,2,3,4,5). A26046

Number of elements in the coprime subsets of the integers 1 to n. A87080

G.f. = theta₄(0,x⁴)/theta₄(0,x). A103258

a(n) = number of triangles that can be formed from the points of a 3 X n grid. A262402

Expansion of ∏_k>=1 (1 - k²*x^k). A292164

Numbers n such that n¹⁰²⁴ + (n+1)¹⁰²⁴ is prime. A274234

Number of Twopins positions. A5684