Properties of the Number 31809

Thirty-One Thousand Eight Hundred Nine

Basics

Value: 31808 → 31809 → 31810

Parity: odd

Prime: No

Previous Prime: 31799

Next Prime: 31817

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 3 × 23 × 461

Divisors: 1, 3, 23, 69, 461, 1383, 10603, 31809

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 111110001000001

Octal: 76101

Duodecimal: 164A9

Hexadecimal: 7c41

Square: 1011812481

Square Root: 178.35077796297946

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

8-step Fibonacci sequence starting with 0,0,0,0,0,1,0,0. A251740

Monotonic ordering of set S generated by these rules: if·and y are in S then 2xy-x-y is in S, and 3 is in S. A192525

Indices of primes in sequence defined by A(0) = 19, A(n) = 10·A(n-1) - 81 for n > 0. A102008

Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 211", based on the 5-celled von Neumann neighborhood. A270899

Numbers k such that k![4] - 2 is prime, where k![4] = A007662(k) = quadruple factorial. A283554

a(n) is the first number that is the start of a string of exactly n consecutive numbers in A358350. A359248

a(n)=a(n-1)*a(n-2)*a(n-3)*(1/a(n-1)+1/a(n-2)+1/a(n-3)) starting with a(1)=a(2)=1 and a(3)=2. A74046

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 41 ones. A31809