Properties of the Number 18239

Eighteen Thousand Two Hundred Thirty-Nine

Basics

Value: 18238 → 18239 → 18240

Parity: odd

Prime: No

Previous Prime: 18233

Next Prime: 18251

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 13 × 23 × 61

Divisors: 1, 13, 23, 61, 299, 793, 1403, 18239

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100011100111111

Octal: 43477

Duodecimal: A67B

Hexadecimal: 473f

Square: 332661121

Square Root: 135.05184189784308

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*(3·n² - 1)/2. A4188

Numbers k with the property that it is possible to write the base 2 expansion of k as concat(a₂,b₂), with a₂>0 and b₂>0 such that, converting a₂ and b₂ to base 10 as a and b, we have σ(a) + σ (b) = σ(k) - k. A258813

a(1)=1, a(2)=2; for n >= 2, a(n+1) = a(n) + sum of prime factors of a(n). A96461

Triangle T(n, k) read by rows: row n gives the coefficients of the row polynomials of the (n+1)-th diagonal sequence of the Sheffer triangle A094816 (special Poisson-Charlier). A290311

Numerators in binomial transform of 1/(n+1)². A97344

Numerators of the partial sums of the binomial transform of 1/(n+1). A97345

Numbers k such that φ(k) + φ(k+1) divides σ(k) + σ(k+1). A67282

a(n) is the number of integer triples (x,y,z) satisfying a system of linear inequalities and congruences specified in the comments. A370349

a(1) = 1, a(2) = 2; for n >= 2, a(n+1) = a(n) + sum of the unique prime factors of a(n). A96460

a(n+1) is the sum of a(n) and the prime factors of a(n), counted with multiplicity. Start with a(0) = 3. A192896