201999 has 8 divisors (see below), whose sum is σ = 307840. Its totient is φ = 115416.

The previous prime is 201997. The next prime is 202001. The reversal of 201999 is 999102.

201999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (201997) and next prime (202001).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 201999 - 2¹ = 201997 is a prime.

It is a Duffinian number.

201999 is a modest number, since divided by 999 gives 201 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4789 + ... + 4830.

It is an arithmetic number, because the mean of its divisors is an integer number (38480).

2²⁰¹⁹⁹⁹ is an apocalyptic number.

201999 is a deficient number, since it is larger than the sum of its proper divisors (105841).

201999 is an equidigital number, since it uses as much as digits as its factorization.

201999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9629.

The product of its (nonzero) digits is 1458, while the sum is 30.

The square root of 201999 is about 449.4429885981. The cubic root of 201999 is about 58.6745462614.

The spelling of 201999 in words is "two hundred one thousand, nine hundred ninety-nine".