Properties of the Number 28161

Twenty-Eight Thousand One Hundred Sixty-One

Basics

Value: 28160 → 28161 → 28162

Parity: odd

Prime: No

Previous Prime: 28151

Next Prime: 28163

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ³ × 7 × 149

Divisors: 1, 3, 7, 9, 21, 27, 63, 149, 189, 447

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 110111000000001

Octal: 67001

Duodecimal: 14369

Hexadecimal: 6e01

Square: 793041921

Square Root: 167.81239525136397

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 g.f. (1-sqrt(1-4·x-4·x²))/(2*(1+x)). A52709

T(n,k) is the number of (n+1) X (k+1) 0..1 arrays with the permanents of all 2 X 2 subblocks equal and nonzero. A204713

Triangle T(n,k) (n>=0, 0 <= k <= n) read by rows giving number of underdiagonal lattice paths from (0,0) to (n,k) using only steps R=(1,0), V=(0,1) and D=(1,2). A71943

Triangle T(n,k) read by rows giving number of underdiagonal lattice paths from (0,0) to (n,k) using steps R=(1,0), V=(0,1) and D=(2,1). A71945

T(n,k)=Number of nXk 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value 2-x(i,j). A230652

T(n,k)=Number of nXk 0..2 black square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value 2-x(i,j). A230661

a(n) = T(0,n), array T given by A048505. A48506

Record indices of A135727(n) = max{ A001281^k(n);k=0,1,2,3... } (3x-1 problem). A135728

Record indices of A135727(n)/n = max{ A001281^k(n);k=0,1,2,3... }/n (3x-1 problem). A135729

Matrix inverse of triangle A101275 (number of Schröder paths). A102051