Properties of the Number 18642

Eighteen Thousand Six Hundred Forty-Two

Basics

Value: 18641 → 18642 → 18643

Parity: even

Prime: No

Previous Prime: 18637

Next Prime: 18661

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 2 × 3 × 13 × 239

Divisors: 1, 2, 3, 6, 13, 26, 39, 78, 239, 478

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100100011010010

Octal: 44322

Duodecimal: A956

Hexadecimal: 48d2

Square: 347524164

Square Root: 136.53570961473778

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 which converge to 2592 under repeated application of the powertrain map of A133500. A135384

Integers i > 1 for which there is no prime p such that i is a solution mod p of x⁴ = 2. A65903

Triangle T, read by rows, where column k of T = column 0 of matrix power T^k+1 for k>0, with column 0 of T = column 1 of T² (shifted). A152406

Column 2 of triangle A152406; also, column 0 of matrix cube of A152406. A152409

Number of integers m in [0..10ⁿ-1] such that m has no digit in common with the last n digits of either m² or m³. A256714

Number of length 1+2 0..n arrays with no three consecutive terms having the sum of any two elements equal to twice the third. A248462

a(1) = 1; a(n) = 1 + a(n-1) + ∑_k=2..n a(floor(n/k)). A351621

Coordination sequence for D₁₃ lattice. A107508

Squarefree composite numbers m such that k - m² < m, where k is the smallest number greater than m² such that rad(k) | m. A362003

Dedekind ψ function: n * ∏_{p∣n, p prime} (1 + 1/p). A1615