Properties of the Number 19866

Nineteen Thousand Eight Hundred Sixty-Six

Basics

Value: 19865 → 19866 → 19867

Parity: even

Prime: No

Previous Prime: 19861

Next Prime: 19867

Digit Sum: 30

Digital Root: 3

Palindrome: No

Factorization: 2 × 3 × 7 × 11 × 43

Divisors: 1, 2, 3, 6, 7, 11, 14, 21, 22, 33

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100110110011010

Octal: 46632

Duodecimal: B5B6

Hexadecimal: 4d9a

Square: 394657956

Square Root: 140.94679847375036

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

a(n) = floor(n*(n-1)*(n-2)/4). A11886

a(n) = n*(n+1)*(2·n+1). A55112

Largest area of a Pythagorean triangle with n as length of one of the three sides (in fact as a leg). A55522

a(n) = largest value of the function rad(m·n*(n - m)) n=2,3,4,..., 0 < m < n where the function rad(k) (also called radical(k)) is the product of distinct prime divisors of k. A147299

Denominator of c(n) = (n²+n+2)/((n+1)*(n+2)*(n+3)). A241269

Smallest area of a Pythagorean triangle with n as length of one of the three sides. A54435

Smallest area of a Pythagorean triangle with n as length of a leg. A54436

Triangle, read by rows, each row n being defined by g.f. ∏_k=1..n (k + x + k·x²), for n >= 0. A322235

a(n) = [x^n-1] ∏_k=1..n (k + x + k·x²), for n >= 1. A322237

Composite numbers divisible by the palindromic sum of their prime factors (counted with multiplicity). A46358