20000

20000, written twenty thousand, is the natural number following 19999 and preceding 20001. In decimal notation it is a round, even number and a composite integer.

Prime factorization and divisors: 20000 = 2^5 × 5^4. Because its prime exponents are (5,4), the number of positive divisors is (5+1)(4+1) = 30. It is divisible by 10, 20, 25, 40, 50, and many other integers; it is also a Harshad number in base 10 since 2+0+0+0+0 = 2 and 20000 is divisible by 2.

Representations: In binary, 20000 is 100111000100000; in hexadecimal, 0x4E20. In Roman numerals, large values are represented with overlines; 20,000 is commonly rendered as XX with a bar over it.

In culture and science: as a round figure, twenty thousand appears in contexts such as crowd counts, budgets, or sample sizes. It is a common milestone or threshold in data reporting.

A notable literary reference is Jules Verne's Twenty Thousand Leagues Under the Sea, a classic science fiction novel published in 1870. The title uses the number twenty thousand to convey a vast, fantastical distance and adventure.

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