Properties of the Number 18821

Eighteen Thousand Eight Hundred Twenty-One

Basics

Value: 18820 → 18821 → 18822

Parity: odd

Prime: No

Previous Prime: 18803

Next Prime: 18839

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 11 × 29 × 59

Divisors: 1, 11, 29, 59, 319, 649, 1711, 18821

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100100110000101

Octal: 44605

Duodecimal: AA85

Hexadecimal: 4985

Square: 354230041

Square Root: 137.18964975536602

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 positive special sums of integer partitions of n. A301854

a(n)³ is smallest cube containing exactly n 6's. A48371

Reversion of y - y² - y⁴ - y⁵. A63023

Products of three distinct strong primes. A363782

a(n+3) = floor( ( a(n) + 2·a(n+1) + 3·a(n+2) )/4 ), with a(0), a(1), a(2) equal to 0, 1, 2. A74732

Numbers whose cubes contain more than half the same digit and do not end in 0. A60814

Least number k such that the square root of {k² + (Prime[n + k] - Prime[n])²} is an integer; or 0 if no such number exists. A66689

Number of n X 4 1..4 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in increasing order. A166824

n is the sum of k nonzero squares for all 2 <= k <= n-14. A18821

Difference between the smallest 10ⁿ-digit member of a twin prime pair and 10^{10ⁿ - 1}. A226704