Properties of the Number 19665

Nineteen Thousand Six Hundred Sixty-Five

Basics

Value: 19664 → 19665 → 19666

Parity: odd

Prime: No

Previous Prime: 19661

Next Prime: 19681

Digit Sum: 27

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 5 × 19 × 23

Divisors: 1, 3, 5, 9, 15, 19, 23, 45, 57, 69

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100110011010001

Octal: 46321

Duodecimal: B469

Hexadecimal: 4cd1

Square: 386712225

Square Root: 140.23195071024293

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 ordered pairs of integer partitions of n where no part of the first is greater than any part of the second. A322439

Expansion of ∏_k>=1 1/(1-x^k+6)^k. A263362

Numbers that are the sum of four third powers in six or more ways. A345148

T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with each row and column prime, read as a base 3 number with top and left being the most significant digits. A262122

Numbers that are the sum of four third powers in exactly six ways. A345149

T(n,k)=Number of nXk arrays of the minimum or maximum value of corresponding elements and their horizontal and vertical neighbors in a random 0..2 nXk array. A217999

Number of primes == 3 (mod 10) less than 10ⁿ. A73506

a(n) = ∑_i=0..n digsum₉(i)³, where digsum₉(i) = A053830(i). A231686

a(1) = 1; a(n) = -∑_k=2..n k³ * a(floor(n/k)). A360658

Expansion of e.g.f.: cosh(sqrt(2)*x)*(1+exp(x)). A88014