Properties of the Number 20561

Twenty Thousand Five Hundred Sixty-One

Basics

Value: 20560 → 20561 → 20562

Parity: odd

Prime: No

Previous Prime: 20551

Next Prime: 20563

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 29 × 709

Divisors: 1, 29, 709, 20561

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101000001010001

Octal: 50121

Duodecimal: BA95

Hexadecimal: 5051

Square: 422754721

Square Root: 143.39107364128355

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

Sums of 5 distinct powers of 4. A38473

a(n) = 1 - 2·n² + 4·n*(1 + 2·n²)/3. A168547

Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 297", based on the 5-celled von Neumann neighborhood. A280614

a(n) = (4·n³ - 6·n² + 8·n + 9 + 3*(-1)ⁿ)/12. A168582

Number of the essentially different permutations of the numbers 0 to n such that the sum of adjacent numbers is a square. A108658

Expansion of ψ(x²) * φ(x⁷) / (f(-x) * f(-x⁷)) in powers of·where φ(), ψ(), f() are Ramanujan θ functions. A193826

Sums of p-th to the q-th prime where p and q are twin primes. A114379

Number of ordered oriented multigraphs on n labeled arcs (with loops). A20561

Maximum period of a totalistic cellular automaton on a connected graph with n nodes (not counting the state of the updated node itself). A357953

Number of (n+2) X (3+2) 0..3 arrays with every 3 X 3 subblock row and column sum equal to 2 3 4 6 or 7 and every 3 X 3 diagonal and antidiagonal sum not equal to 2 3 4 6 or 7. A252162