Properties of the Number 19891

Nineteen Thousand Eight Hundred Ninety-One

Basics

Value: 19890 → 19891 → 19892

Parity: odd

Prime: Yes

Previous Prime: 19889

Next Prime: 19913

Digit Sum: 28

Digital Root: 1

Palindrome: Yes

Factorization: 19891

Divisors: 1, 19891

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100110110110011

Octal: 46663

Duodecimal: B617

Hexadecimal: 4db3

Square: 395651881

Square Root: 141.03545653487282

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

Palindromic primes: prime numbers whose decimal expansion is a palindrome. A2385

Palindromic in bases 10 and 32. A99165

Discriminants of imaginary quadratic fields with class number 25 (negated). A56987

Primes p such that q-p = 22, where q is the next prime after p. A61779

Mother primes of order 8. A136067

Permutation of natural numbers: a(1) = 1, a(2n) = A091242(a(n)), a(2n+1) = A014580(a(n)), where A091242(n) = binary code for n-th reducible polynomial over GF(2) and A014580(n) = binary code for n-th irreducible polynomial over GF(2). A246202

Primes having only {1, 8, 9} as digits. A385783

G.f.: ∏_m>0 (1+x^m+2!*x^2·m). A293204

Palindromic primes using only nonprime digits (0,1,4,6,8,9). A83185

Palindromic primes which are a member of a twin prime pair. A83840