Properties of the Number 91821

Ninety-One Thousand Eight Hundred Twenty-One

Basics

Value: 91820 → 91821 → 91822

Parity: odd

Prime: No

Previous Prime: 91813

Next Prime: 91823

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 3 × 127 × 241

Divisors: 1, 3, 127, 241, 381, 723, 30607, 91821

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10110011010101101

Octal: 263255

Duodecimal: 45179

Hexadecimal: 166ad

Square: 8431096041

Square Root: 303.0198013331802

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 (n+2) X (k+2) 0..1 arrays with no 3 X 3 subblock diagonal sum 1 and no antidiagonal sum 1 and no row sum 1 and no column sum 1. A255101

Triangle read by rows, T(n, 1) = 1 and T(n,k) = q^k*T(n-1, k) + T(n-1, k-1) for 2 <= k <= n, n >= 1, with q=2. A176242

Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum 1 and no antidiagonal sum 1 and no row sum 1 and no column sum 1. A255095

a(n) is the number of integer sequences b(0..n) of length n+1, with 0 <= b(k) <= k! and monotonic b(k) <= b(k+1). A355129

a(n) counts the one-bits in the binary representation of n when we cycle from left to right through the individual bits of n, restarting at the leftmost bit after the rightmost is reached and performing n bitwise steps in total. A91821