Properties of the Number 1811

One Thousand Eight Hundred Eleven

Basics

Value: 1810 → 1811 → 1812

Parity: odd

Prime: Yes

Previous Prime: 1801

Next Prime: 1823

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 1811

Divisors: 1, 1811

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 11100010011

Octal: 3423

Duodecimal: 106B

Hexadecimal: 713

Square: 3279721

Square Root: 42.555845661906424

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

Primes > 1000 in which every substring of length 3 is also prime. A69489

Numbers > 1000 such that all the substrings of length = 3 are primes (substrings with leading '0' are considered to be nonprime). A211684

Primes p such that q = (p² + 1)/2 is also a prime. A48161

Prime numbers > 1000 such that all the substrings of length >= 3 are primes (substrings with leading '0' are considered to be nonprime). A211685

Primes of the form 2·n² + 11. A50265

Numbers n such that n, 2n+1, and 4n+3 all prime. A7700

Discriminants of imaginary quadratic fields with class number 23 (negated). A46020

Lucasian primes: p == 3 (mod 4) with 2·p+1 prime. A2515

Primes with only nonprime decimal digits. A34844

Primes p such that p² + p + 1 is prime. A53182