Properties of the Number -21688

Twenty-One Thousand Six Hundred Eighty-Eight

Basics

Value: -21689 → -21688 → -21687

Parity: even

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 25

Digital Root: 7

Palindrome: No

Factorization: 2 ³ × 2711

Divisors: 1, 2, 4, 8, 2711, 5422, 10844, 21688

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: -101010010111000

Octal: -52270

Duodecimal: -10674

Hexadecimal: -54b8

Square: 470369344

Square Root: 147.26846234004074

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 ways to choose a multiset of strict partitions, or odd partitions, of odd numbers, whose weights sum to n. A300300

Composites whose prime factorization in base 5 is an anagram of the number in base 5. A260049

Number of triangular regions in a "frame" of size n X n (see Comments in A331776 for definition), divided by 4. A332595

Trajectory of 1001 under "3x+1" map. A100709

E.g.f. A(x) satisfies: A(x/(1-x))/(1-x) = (1/x) * d/dx x²*A(x)/2. A209884

Numbers n such that 6·10ⁿ + 4·R_n + 3 is prime, where R_n = 11...1 is the repunit (A002275) of length n. A103036

Number of length 3+3 0..n arrays with some disjoint pairs in every consecutive four terms having the same sum. A247535

Triangle read by rows: Kreweras's "Rule A₄ left thickness" numbers. A259099

a(n) is the first position where the digits of n occur simultaneously in the decimal expansions of π and e. A381980

Expansion of g.f. -x*(5·x⁷-20·x⁶-2·x⁵+54·x⁴+7·x³-20·x²-8·x-1)/((x⁴-x³-3·x²+x+1)*(x⁴+x³-3·x²-x+1)). A122013