Properties of the Number 20619

Twenty Thousand Six Hundred Nineteen

Basics

Value: 20618 → 20619 → 20620

Parity: odd

Prime: No

Previous Prime: 20611

Next Prime: 20627

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ² × 29 × 79

Divisors: 1, 3, 9, 29, 79, 87, 237, 261, 711, 2291

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000010001011

Octal: 50213

Duodecimal: BB23

Hexadecimal: 508b

Square: 425143161

Square Root: 143.59317532529184

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

Indices of primes followed by a gap (distance to next larger prime) of 44. A320720

a(n) = (2·n-1)*(n² -n +6)/6. A49480

Number of strict compositions of n with all adjacent parts (x, y) satisfying x < 2y and y < 2x. A342341

For 1<=x<=n, 1<=y<=n, write gcd(x,y) = u·x+v·y with u,v minimal; a(n) = sum of the values of u²+v². A345434

Numbers k such that σ(k-φ(k)) = φ(k). A70170

Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where column k is the expansion of e.g.f. B(x)^k, where B(x) is the e.g.f. of A384760. A384761

Partial sums of A061262. A176661

Smallest nonempty set S containing prime divisors of 8k+6 for each k in S. A20619