Properties of the Number 19728

Nineteen Thousand Seven Hundred Twenty-Eight

Basics

Value: 19727 → 19728 → 19729

Parity: even

Prime: No

Previous Prime: 19727

Next Prime: 19739

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 2 ⁴ × 3 ² × 137

Divisors: 1, 2, 3, 4, 6, 8, 9, 12, 16, 18

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 100110100010000

Octal: 46420

Duodecimal: B500

Hexadecimal: 4d10

Square: 389193984

Square Root: 140.4563989286355

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) = coefficient of xⁿ in A(x) such that 2 = ∑_n=-oo..+oo (-x)ⁿ * (2·A(x) + x^n-1)ⁿ⁺¹. A359712

Numbers k such that k and 4·k are anagrams. A23088

Number of partitions in parts not of the form 15k, 15k+1 or 15k-1. Also number of partitions with no part of size 1 and differences between parts at distance 6 are greater than 1. A35955

Number of weak peaks in all Motzkin paths of length n. A weak peak of a Motzkin path is a vertex on the top of a hump. A hump is an upstep followed by 0 or more flatsteps followed by a downstep. For example, the Motzkin path u·duu·h*h·dd, where u=(1,1), h=(1,0), d(1,-1), has 4 weak peaks (shown by the stars). A247287

Number of (w,x,y,z) with all terms in {1,...,n} and w²>x²+y²+z². A212094

Numbers k such that k·p is divisible by k+p, where p > 0 and p = A007954(k) = the product of digits of k. A334679

a(n) = ∑_{k=0..floor(n/3)} 2^n-3·k * binomial(k,n-3·k)². A387516

Numbers k such that each of k, k+1, k+2, and k+4 is a sum of two squares. A328224

Product between n-th prime and next perfect square. A229497

θ series of 8-dimensional strongly 6-modular lattice O(6) with minimal norm 3. A29720