Properties of the Number 21267

Twenty-One Thousand Two Hundred Sixty-Seven

Basics

Value: 21266 → 21267 → 21268

Parity: odd

Prime: No

Previous Prime: 21247

Next Prime: 21269

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 17 × 139

Divisors: 1, 3, 9, 17, 51, 139, 153, 417, 1251, 2363

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001100010011

Octal: 51423

Duodecimal: 10383

Hexadecimal: 5313

Square: 452285289

Square Root: 145.8320952328396

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 n-stacks with strictly receding walls, or the number of Type A partitions of n in the sense of Auluck (1951). A1522

This table shows the coefficients of combinatorial formulas needed for generating the sequential sums of p-th powers of binomial coefficients C(n,6). The p-th row (p>=1) contains a(i,p) for i=1 to 6·p-5, where a(i,p) satisfies ∑_i=1..n C(i+5,6)^p = 7·C(n+6,7) * ∑_i=1..6·p-5 a(i,p) * C(n-1,i-1)/(i+6). A87110

Dirichlet g.f.: ∏_k>=2 1 / (1 - k^-s)^k². A329125

Numbers that are the sum of seven fourth powers in six or more ways. A345572

Numbers that are the sum of seven fourth powers in seven or more ways. A345573

Numbers that are the sum of seven fourth powers in eight or more ways. A345574

Numbers that are the sum of seven fourth powers in nine or more ways. A345575

Numbers that are the sum of seven fourth powers in exactly nine ways. A345831

Numbers·such that the sum of all their cyclic permutations is equal to that of all cyclic permutations of σ(x) and all cyclic permutations of Euler totient function φ(x). A247317

a(n) = 2·a(n-1) - a(n-2) - a(n-4). A131041