Properties of the Number 21947

Twenty-One Thousand Nine Hundred Forty-Seven

Basics

Value: 21946 → 21947 → 21948

Parity: odd

Prime: No

Previous Prime: 21943

Next Prime: 21961

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 17 × 1291

Divisors: 1, 17, 1291, 21947

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101010110111011

Octal: 52673

Duodecimal: 1084B

Hexadecimal: 55bb

Square: 481670809

Square Root: 148.14519904472098

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

Generalized Lucas numbers. A6492

Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 350", based on the 5-celled von Neumann neighborhood. A281284

Fibonacci sequence beginning 2, 21. A294116

a(n) = K₃(n) = ∑_k>=0 A090285(3,k)*2^k*binomial(n,k). a(n) = (4·n³+30·n²+56·n+15)/3. A90294

a(n) = (n³ + 4·n² - n)/2. A162260

Row sums of triangular table A138612. A166020

Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite DDR = Deca-dodecasil 3R[Si120O240]qR starting with a T2 atom. A19106

Number of partitions of n satisfying cn(2,5) + cn(3,5) <= cn(0,5). A39861

Decimal expansion of 1/943. A21947