Properties of the Number 21832

Twenty-One Thousand Eight Hundred Thirty-Two

Basics

Value: 21831 → 21832 → 21833

Parity: even

Prime: No

Previous Prime: 21821

Next Prime: 21839

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 2 ³ × 2729

Divisors: 1, 2, 4, 8, 2729, 5458, 10916, 21832

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 101010101001000

Octal: 52510

Duodecimal: 10774

Hexadecimal: 5548

Square: 476636224

Square Root: 147.75655653811103

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

T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. A302877

Triangle read by rows: The n-th row is constructed by forming the partial sums of the previous row, reading from the right and if n is a triangular number repeating the final term. A99964

Principal diagonal of the convolution array A213781. A213782

Second column of triangle in A099964. A99968

Number of two-sided n-step prudent walks ending on the northeast corner of their box, avoiding two or more consecutive west steps and south steps. A190587

a(n) = 3·a(n-1) - a(n-2) - 3·a(n-3) + 2·a(n-4), where a(0) = 2, a(1) = 4, a(2) = 8, a(3) = 18. A288206

Number of n X 2 binary arrays indicating whether each 2 X 2 subblock of a larger binary array has lexicographically increasing rows and columns, for some larger (n+1) X 3 binary array with rows and columns of the latter in lexicographically nondecreasing order. A227085

Number of 2 X n 0..2 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. A280481

Number of 4Xn 0..1 arrays with every element equal to 0, 1, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. A302879

a(n) = 1 - n + (2ⁿ⁺² - (-1)ⁿ)/3. A322783