Properties of the Number 6669

Six Thousand Six Hundred Sixty-Nine

Basics

Value: 6668 → 6669 → 6670

Parity: odd

Prime: No

Previous Prime: 6661

Next Prime: 6673

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 3 ³ × 13 × 19

Divisors: 1, 3, 9, 13, 19, 27, 39, 57, 117, 171

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 1101000001101

Octal: 15015

Duodecimal: 3A39

Hexadecimal: 1a0d

Square: 44475561

Square Root: 81.6639455328972

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

Coordination sequence for 3D uniform tiling formed by stacking parallel layers of the 4.8.8 2D tiling (cf. A008576). A299259

9 times the triangular numbers A000217. A27468

Triangle read by rows: T(n,k) is the number of permutations of [n] having k-1 alternating descents (1<=k<=n). The index i is an alternating descent of a permutation p if either i is odd and p(i)>p(i+1), or i is even and p(i)<p(i+1). A145876

a(n) = n³ + (n+1)³ + (n+2)³. A27602

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

Number of partitions of n such that the set of even parts has only one element. A90867

a(n) = n³ - n*(n+1)/2. A160378

Numbers in which 6 outnumbers all other digits together. A292736

5-almost primes with semiprime digits (digits 4, 6, 9 only). A111697

Square array A(n,k) = A341527(A246278(n,k)), read by falling antidiagonals; denominators of the columnwise first quotients of A341605/A341606. A341627