Properties of the Number 21445

Twenty-One Thousand Four Hundred Forty-Five

Basics

Value: 21444 → 21445 → 21446

Parity: odd

Prime: No

Previous Prime: 21433

Next Prime: 21467

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 5 × 4289

Divisors: 1, 5, 4289, 21445

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101001111000101

Octal: 51705

Duodecimal: 104B1

Hexadecimal: 53c5

Square: 459888025

Square Root: 146.44111444536333

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

Numbers k such that 100k+1, 100k+3, 100k+7, 100k+9 are all primes. A64687

Expansion of ∏_{k > 0} (1 + A147665(k)*x^k). A147871

Numbers k such that 15·2^k + 1 is prime. A2258

Number of Dyck paths of semilength n avoiding the pattern U⁴ D⁴ U D. A225691

Numbers k such that A339549(k) = A339549(k+1). A339550

Numbers whose concatenation of prime factors (with multiplicity) is a square. A38693

Number of 3 X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing. A229446

Reduced numerators of the Kirchhoff sum index for the n-halved cube graph. A290367

Number of 3Xn 0..2 arrays with no element having a strict majority of its horizontal and antidiagonal neighbors equal to itself plus one mod 3, with upper left element zero (rock paper and scissors drawn positions). A231857

Number of (n+1) X (5+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically. A253453