Properties of the Number 21844

Twenty-One Thousand Eight Hundred Forty-Four

Basics

Value: 21843 → 21844 → 21845

Parity: even

Prime: No

Previous Prime: 21841

Next Prime: 21851

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 2 ² × 43 × 127

Divisors: 1, 2, 4, 43, 86, 127, 172, 254, 508, 5461

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010101010100

Octal: 52524

Duodecimal: 10784

Hexadecimal: 5554

Square: 477160336

Square Root: 147.79715829473852

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

Expansion of (1-x+2·x²)/((1+x)*(1-2·x)). A97073

a(n) = a(n-1) + 2·a(n-2) + 2, for n>=3, where a(0)= 1, a(1)= 2, a(2)= 4. A26644

Numerators in Taylor series for tan(x). Also from Taylor series for tanh(x). A2430

a(n) = -a(n-1) + 2·a(n-2), a(0)=1, a(1)=2. A84247

a(n) = (4/3)*(4ⁿ - 1). A80674

Expansion of x*(1+2·x)/((1+x)*(1-x)*(1-2·x)). A84639

Numerators of the coefficients in the Taylor expansion of sec(x) + tan(x) around x=0. A99612

Intrinsic 10-palindromes: n is an intrinsic k-palindrome if it is a k-digit palindrome in some base. A60947

The left hand column of the triangle A160468. A160469

Expansion of x³ / ((x-1)*(2·x-1)*(x²-x+1)). A111927