Properties of the Number 19912

Nineteen Thousand Nine Hundred Twelve

Basics

Value: 19911 → 19912 → 19913

Parity: even

Prime: No

Previous Prime: 19891

Next Prime: 19913

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 2 ³ × 19 × 131

Divisors: 1, 2, 4, 8, 19, 38, 76, 131, 152, 262

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100110111001000

Octal: 46710

Duodecimal: B634

Hexadecimal: 4dc8

Square: 396487744

Square Root: 141.10988625890107

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

Triangle of Eulerian numbers with rows multiplied by 1 + x. A8518

Triangle T(n, k) = T(n-1, k) + T(n-1, k-1) + j·prime(j)*T(n-2, k-1) with j=3, read by rows. A153648

Number of degree 3 vertices in the n-Sierpinski carpet graph. A365607

Triangle T(n,k) read by rows giving number of fixed 4 X k polyominoes with n cells (n >= 4, 1<=k<=n-3). A59680

Triangle, read by rows, that transforms diagonals in the array A274390 of coefficients in successive iterations of Euler's tree function (A000169). A274570

Number of pairs of functions (f,g) from a set of n elements into itself satisfying f(g(x)) = f(g(g(x))). A239785

Column 1 of triangle A274570. A274572

Triangle T(n,k) giving number of fixed 5 X k polyominoes with n cells (n >= 5, 1<=k<=n-4). A59681

a(n) = (round(c^prime(n)) - 1)/prime(n), where c is the pentanacci constant (A103814). A239564

Expansion of (1+3·x+x²) / (1-x-5·x²-2·x³). A384647