Properties of the Number 19561

Nineteen Thousand Five Hundred Sixty-One

Basics

Value: 19560 → 19561 → 19562

Parity: odd

Prime: No

Previous Prime: 19559

Next Prime: 19571

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 31 × 631

Divisors: 1, 31, 631, 19561

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100110001101001

Octal: 46151

Duodecimal: B3A1

Hexadecimal: 4c69

Square: 382632721

Square Root: 139.86064492915796

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

Number of integer partitions of n with all distinct lengths of maximal gapless runs (decreasing by 0 or 1). A384884

T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3 or 5 king-move adjacent elements, with upper left element zero. A297951

Strong pseudoprimes to base 8. A20234

T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. A301354

Odd composite numbers n, such that n, n+d, n·d and n/d are all odious (A000069) for every divisor d of n. A231558

Expansion of ∑_k>=2 x^Fibonacci(k)/(1 - x^Fibonacci(k)) / ∏_k>=2 (1 - x^Fibonacci(k)). A281689

G.f. satisfies A(x) = exp( ∑_k>=1 ((-2)^k + A(x^k)) * x^k/k ). A363578

Divisors of 2⁴⁵ - 1. A3550

Strong pseudoprimes to base 44. A20270

Strong pseudoprimes to base 64. A20290