Properties of the Number 20911

Twenty Thousand Nine Hundred Eleven

Basics

Value: 20910 → 20911 → 20912

Parity: odd

Prime: No

Previous Prime: 20903

Next Prime: 20921

Digit Sum: 13

Digital Root: 4

Palindrome: No

Factorization: 11 × 1901

Divisors: 1, 11, 1901, 20911

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101000110101111

Octal: 50657

Duodecimal: 10127

Hexadecimal: 51af

Square: 437269921

Square Root: 144.60636223901076

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 with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..2 introduced in row major order. A231263

Number of 3's in the last section of the set of partitions of n. A182713

Third row of Pascal-(1,4,1) array A081579. A81587

G.f.: A(x) = x/Series_Reversion(G(x)) where x·A(G(x)) = G(x) is the g.f. of A000699. A178685

Numbers n such that 8·10ⁿ + 9 is prime. A103070

Pyramid game person numbers that have integer solutions. A135051

The maximum integer dimension in which the volume of the hypersphere of radius n remains larger than 1. A177677

Row square-sums of triangle A210658. A182018

Number of second differences of arrays of length 5 of numbers in 0..n. A228220

Number of (n+1) X (2+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..2 introduced in row major order. A231257