Properties of the Number 42168

Forty-Two Thousand One Hundred Sixty-Eight

Basics

Value: 42167 → 42168 → 42169

Parity: even

Prime: No

Previous Prime: 42157

Next Prime: 42169

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 2 ³ × 3 × 7 × 251

Divisors: 1, 2, 3, 4, 6, 7, 8, 12, 14, 21

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 1010010010111000

Octal: 122270

Duodecimal: 204A0

Hexadecimal: a4b8

Square: 1778140224

Square Root: 205.3484842895121

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

Amicable triples: numbers such that σ(x) = σ(y) = σ(z) = x+y+z, x<y<z. We order these triples according to the common value of σ. Sequence gives z numbers. A125492

T(n,k)=4-loop graph coloring a rectangular array: number of nXk 0..8 arrays where 0..8 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 0,5 5,6 6,0 0,7 7,8 8,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph. A223297

Column 8 of array illustrated in A089574 and related to A034261. A109126

Triangle read by rows: T(n,k) is the number of permutations of [n] having k cycles with at most 2 alternating runs (it is assumed that the smallest element of the cycle is in the first position), 0<=k<=n. A187247

Numbers that belong to at least one amicable tuple. A255215

Sorted elements of table (A035002) of a(m,n) = sum(a(m-k,n), k=1..m-1)+sum(a(m,n-k), k=1..n-1). A35001

4-loop graph coloring a rectangular array: number of n X n 0..8 arrays where 0..8 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 0,5 5,6 6,0 0,7 7,8 8,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph. A223289

4-loop graph coloring a rectangular array: number of n X 3 0..8 arrays where 0..8 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 0,5 5,6 6,0 0,7 7,8 8,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph. A223292

Number of nX4 0..1 arrays with every element unequal to 1, 2, 3, 6 or 8 king-move adjacent elements, with upper left element zero. A305485

Triangular array read by rows: T(n,k) is the number of simple labeled graphs on n nodes with unicyclic components having exactly k nodes with degree 1; n>=3, 0<=k<=n-3. A217763