Properties of the Number 20871

Twenty Thousand Eight Hundred Seventy-One

Basics

Value: 20870 → 20871 → 20872

Parity: odd

Prime: No

Previous Prime: 20857

Next Prime: 20873

Digit Sum: 18

Digital Root: 9

Palindrome: No

Factorization: 3 ³ × 773

Divisors: 1, 3, 9, 27, 773, 2319, 6957, 20871

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101000110000111

Octal: 50607

Duodecimal: 100B3

Hexadecimal: 5187

Square: 435598641

Square Root: 144.46798953401407

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

T(n,k)=Number of (n+1)X(k+1) 0..2 arrays containing all values 0..2 with every 2X2 subblock having two distinct values, and new values 0..2 introduced in row major order. A210052

Triangle, read by rows, that transforms diagonals in the table of coefficients in the successive iterations of g.f. of A236960 such that column 0 equals T(n,0) = nⁿ. A236961

Numbers k such that k and k+1 are both of the form p·q³ where p and q are distinct primes. A215173

Location (x,y) of the first n·n square of composite Gaussian integers in the first quadrant. A225073

Number of nX2 0..1 arrays with every element equal to 0, 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. A300374

Number of partitions of n with up to two distinct kinds of 1. A320689

Number of (n+1)X4 0..2 arrays containing all values 0..2 with every 2X2 subblock having two distinct values, and new values 0..2 introduced in row major order. A210047

Location·of the first n·n square of composite Gaussian integers in the first quadrant. A225074

Number of (n+1) X (4+1) 0..1 arrays with every 2 X 2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically. A253393

Numbers k such that A307437(k) is divisible by 3. A342037