Properties of the Number 21766

Twenty-One Thousand Seven Hundred Sixty-Six

Basics

Value: 21765 → 21766 → 21767

Parity: even

Prime: No

Previous Prime: 21757

Next Prime: 21767

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 2 × 10883

Divisors: 1, 2, 10883, 21766

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010100000110

Octal: 52406

Duodecimal: 1071A

Hexadecimal: 5506

Square: 473758756

Square Root: 147.53304714537688

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, read by rows, where row n equals the coefficients of y^k in R_n-1(y+y²) for k=2..n, where R_n(y) is the n-th row polynomial in y for n>=2 with R₂(y)=y². A187115

Monotonic subsequence of A051169. A51610

Smallest number m such that 2·m - p is composite for the first n primes p. A51169

a(n) = a(n-1) + a(n-2) + 3·a(n-4) - 2·a(n-5) for n >= 5, where a(0) = 2, a(1) = 4, a(2) = 8, a(3) = 13, a(4) = 26. A288925

a(n) = sum of the side lengths of the minimum containing squares of all partitions of n. A368985

Consecutive terms of A065966 which are also consecutive integers. A65976

Numbers k such that A240718(k) = 0. A307818

Consider a number of k digits n = d_k*10^k-1 + d_k-1*10^k-2 + … + d₂*10 + d₁. Sequence lists the numbers n such that σ(n)-n = ∑_i=1..k-1{σ(∑_j=1..i{d_k-j+1*10^i-j})} - ∑_i=1..k-1{σ(∑_j=1..i{d_j*10^j-1})} (see example below). A240903

Decimal expansion of 1/762. A21766

Minimal index of order n Stanley's antimagic square composed of Smith numbers. A225133