Properties of the Number 21910

Twenty-One Thousand Nine Hundred Ten

Basics

Value: 21909 → 21910 → 21911

Parity: even

Prime: No

Previous Prime: 21893

Next Prime: 21911

Digit Sum: 13

Digital Root: 4

Palindrome: No

Factorization: 2 × 5 × 7 × 313

Divisors: 1, 2, 5, 7, 10, 14, 35, 70, 313, 626

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010110010110

Octal: 52626

Duodecimal: 1081A

Hexadecimal: 5596

Square: 480048100

Square Root: 148.02026888233922

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

Weird numbers: abundant (A005101) but not pseudoperfect (A005835). A6037

Unitary weird numbers: unitary abundant (A034683) but not unitary pseudoperfect (A293188). A64114

T(n,k)=Number of length n+4 0..k arrays with every five consecutive terms having the maximum of some two terms equal to the minimum of the remaining three terms. A254698

Nonexponential weird numbers: nonexponential abundant numbers (A348604) that are not equal to the sum of any subset of their nonexponential divisors. A348631

T(n, k) = kⁿ*U(n, (1/k + k)/2) + (n + 1)^{k - 1}*U(k - 1, (1/(n + 1) + n + 1)/2), where U(n,x) is the n-th Chebyshev polynomial of the second kind, square array read by antidiagonals (n >= 0, k >= 1). A173590

(1+e)-weird numbers: (1+e)-abundant numbers k such that no subset of the aliquot (1+e)-divisors of k sums to k. A349285

Coordination sequence for MgZn2, Mg position. A9939

Solutions y of the Mordell equation y² = x³ - 3a² + 1 for a = 0,1,2, ... (solutions·are given by the sequence A000466). A173202

Number of length 1+4 0..n arrays with every five consecutive terms having the maximum of some two terms equal to the minimum of the remaining three terms. A254699

Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 5 or 7 king-move adjacent elements, with upper left element zero. A304922