Properties of the Number 19669

Nineteen Thousand Six Hundred Sixty-Nine

Basics

Value: 19668 → 19669 → 19670

Parity: odd

Prime: No

Previous Prime: 19661

Next Prime: 19681

Digit Sum: 31

Digital Root: 4

Palindrome: No

Factorization: 13 × 17 × 89

Divisors: 1, 13, 17, 89, 221, 1157, 1513, 19669

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: Yes

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100110011010101

Octal: 46325

Duodecimal: B471

Hexadecimal: 4cd5

Square: 386869561

Square Root: 140.24621207005913

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) = n*(n² + 1)/2. A6003

Numbers k such that k and k + 1 are both lazy-Lucas-Niven numbers (A351719). A351720

a(n) = (2·n + 1)*(5·n + 1). A33571

Composite numbers k of the form 4u+1 for which the odd part of φ(k) divides k-1. A339870

Odd composite numbers k such that A053575(k) [the odd part of φ] divides k-1. A339880

Odd composite integers m such that A014448(m) == 4 (mod m). A335670

a(n) = (n - 1)*(4·n² - 8·n + 5). A317297

Row sums of the triangular array A246696. A246697

Odd composite integers m such that A054413(m-J(m,53)) == 0 (mod m), where J(m,53) is the Jacobi symbol. A340096

Number of primes of the form 8k+7 less than 10ⁿ. A91129