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Properties of the Number 21266

Twenty-One Thousand Two Hundred Sixty-Six

Basics

Value: 21265 → 21266 → 21267

Parity: even

Prime: No

Previous Prime: 21247

Next Prime: 21269

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 2 × 7 3 × 31

Divisors: 1, 2, 7, 14, 31, 49, 62, 98, 217, 343

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001100010010

Octal: 51422

Duodecimal: 10382

Hexadecimal: 5312

Square: 452242756

Square Root: 145.8286665919976

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

Numbers k such that sopfr(k + sopfr(k)) = sopfr(k) + sopfr(sopfr(k)), where sopfr = A001414. A376851
Numbers m such that the GCD of the x's that satisfy σ(x) = m is 4. A241649
Integers, a, which are the solutions to the equation a2 + b3 = c4, with integers a, b > 0, and indexed off of A242183. A242184
Numerators of continued fraction convergents to sqrt(209). A41388
Number of right triangles on a (n+1)X9 grid. A189813
Total number of distinct sequences for the number of double occupancy in the underlying Fermion problem (see comment), i.e., the number of distinct hopping sequences (cf. A198761, A225823) in four-colored rooted trees with n nodes, starting and ending with the same coloring in two colors (cf. A198760, corresponding to zero double-occupancy). A240605
Numbers k such that the number of prime divisors of the k-th Catalan number (counted with multiplicity) divides k. A121612
T(n,k)=Number of right triangles on a (n+1)X(k+1) grid. A189814
Decimal expansion of 1/262. A21266