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Properties of the Number 20493

Twenty Thousand Four Hundred Ninety-Three

Basics

Value: 20492 → 20493 → 20494

Parity: odd

Prime: No

Previous Prime: 20483

Next Prime: 20507

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 4 × 11 × 23

Divisors: 1, 3, 9, 11, 23, 27, 33, 69, 81, 99

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000000001101

Octal: 50015

Duodecimal: BA39

Hexadecimal: 500d

Square: 419963049

Square Root: 143.1537634852818

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*(n+1)*(11·n+1)/6. A132112
Non-palindromic numbers n such that φ(n) = φ(reversal(n)). A97647
Number of nondividing sets on {1,2,...,n}. A51014
Number of inequivalent (ordered) solutions to n2 = sum of 8 squares of integers >= 0. A65462
Smallest odd number k such that p(2m)-2p(m)=k has exactly n solutions (where p(m) = m-th prime). A69890
Nonsquarefree numbers k such that A276086(A003415(k)) <= k, where A003415 is the arithmetic derivative and A276086 is the primorial base exp-function. A392873
Number of (n+1)X(7+1) 0..1 arrays with every 2X2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically. A253396
Numbers n such that n | 12n + 11n + 10n + 9n + 8n + 7n. A57257
T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with every 2X2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically. A253397
Numbers k such that d(k) (number of divisors) divides φ(k) (Euler function) divides σ(k) (sum of divisors). A20493