Properties of the Number 21669

Twenty-One Thousand Six Hundred Sixty-Nine

Basics

Value: 21668 → 21669 → 21670

Parity: odd

Prime: No

Previous Prime: 21661

Next Prime: 21673

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 3 × 31 × 233

Divisors: 1, 3, 31, 93, 233, 699, 7223, 21669

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010010100101

Octal: 52245

Duodecimal: 10659

Hexadecimal: 54a5

Square: 469545561

Square Root: 147.20394016465727

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

Numbers k such that k³ contains a pandigital substring. A115933

a(n) = ∑_k=0..n (-1)^k * binomial(n+k-1,n-k) * Fibonacci(k+1). A390850

Maximum determinant that can be formed from the optimal set of nonnegative 3 X 3 matrix elements <=n, which maximize the number of different determinants given in A099834. A99815

Number of partitions of n in which exactly one odd part is repeated and even parts are unrestricted. A353903

Numbers n such that (2ⁿ⁺⁷*5ⁿ⁺⁵ - 204979)/9 is prime (n > 0). A266421

Decimal expansion of 1/665. A21669