Properties of the Number 2666

Two Thousand Six Hundred Sixty-Six

Basics

Value: 2665 → 2666 → 2667

Parity: even

Prime: No

Previous Prime: 2663

Next Prime: 2671

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 2 × 31 × 43

Divisors: 1, 2, 31, 43, 62, 86, 1333, 2666

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001101010

Octal: 5152

Duodecimal: 1662

Hexadecimal: a6a

Square: 7107556

Square Root: 51.633322573702344

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

Number of subsets {x(1),x(2),...,x(k)} of {1,2,...,n} such that all differences |x(i)-x(j)| are distinct. A143823

a(n) = 2*(n² - n + 1). A51890

a(n) = A005449(n) - 1, where A005449 = second pentagonal numbers. A95794

Number T(n,k) of equivalence classes of ways of placing k 4 X 4 tiles in an n X 9 rectangle under all symmetry operations of the rectangle; irregular triangle T(n,k), n>=4, 0<=k<=2·floor(n/4), read by rows. A238583

a(n) = n*(n + 19). A132762

Beastly (or hateful) numbers: numbers containing the string 666 in their decimal expansion. A51003

Positive integers n such that n¹⁰ + 1 is semiprime. A105078

T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. A302224

T(n,k) = number of arrays of median of three adjacent elements of some length n+2 0..k array, with no adjacent equal elements in the latter. A229012

Triangle read by rows: T(n,k) is the number of compositions of n having k distinct parts (n>=1, 1<=k<=floor((sqrt(1+8·n)-1)/2)). A235998