Properties of the Number 20309

Twenty Thousand Three Hundred Nine

Basics

Value: 20308 → 20309 → 20310

Parity: odd

Prime: No

Previous Prime: 20297

Next Prime: 20323

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 23 × 883

Divisors: 1, 23, 883, 20309

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 100111101010101

Octal: 47525

Duodecimal: B905

Hexadecimal: 4f55

Square: 412455481

Square Root: 142.50964879614293

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

Decimal representation of the diagonal from the corner to the origin of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 534", based on the 5-celled von Neumann neighborhood. A288983

a(n) = ∑_{i∣n, j∣n, k∣n} i·j*k/gcd(i,j,k). A344133

G.f. A(x) satisfies A(A(A(..(A(x))..))) = B(x) (6th self-COMPOSE of A) such that the coefficients of B(x) consist only of numbers {1,2,3,..,6}, with B(0) = 0. A112113

Integer part of log(nⁿ)^sqrt(n). A62455

Indices of primes in sequence defined by A(0) = 71, A(n) = 10·A(n-1) - 9 for n > 0. A101128

Numbers k such that the representation of k² is a substring of that of k!, in base 10. A113621

Product of two nonconsecutive primes p and q that divides the sum of primes between p and q, exclusively. A200721

Strong pseudoprimes to base 83. A20309

Number of nX4 0..1 arrays with each 1 adjacent to 3, 4 or 5 king-move neighboring 1s. A296986