Properties of the Number 18689

Eighteen Thousand Six Hundred Eighty-Nine

Basics

Value: 18688 → 18689 → 18690

Parity: odd

Prime: No

Previous Prime: 18679

Next Prime: 18691

Digit Sum: 32

Digital Root: 5

Palindrome: No

Factorization: 11 × 1699

Divisors: 1, 11, 1699, 18689

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100100100000001

Octal: 44401

Duodecimal: A995

Hexadecimal: 4901

Square: 349278721

Square Root: 136.70771741200275

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 symmetric ways of folding a strip of n labeled stamps. A560

The internal state of the Sinclair ZX81 and Spectrum random number generator. A357907

Expansion of (1+3·x+14·x²-10·x³-10·x⁴+16·x⁵+15·x⁶-15·x⁷-2·x⁸+4·x⁹+8·x¹⁰) / ((1+4·x²)*(1-x²+x⁴)*(1+x²)²). A112522

Semiprimes p·q such that p·q+p+q, p·q-(p+q), p·q+2*(p+q) and p·q-2*(p+q) are all primes. A356765

Odd nonprimes n such that n+d+1 is prime for all divisors d of n. A187554

Number of 2Xn integer arrays with each element equal to the number of horizontal and antidiagonal neighbors exactly one smaller than itself. A266102

Composite numbers that contain only nonprime digits and whose prime factors contain only nonprime digits. A383934

Number of fixed points on row n of triangle A391930. A391929

Number of (n+1)X(n+1) -6..6 symmetric matrices with every 2X2 subblock having sum zero and three or four distinct values. A211258

Divisors of 861. A18689