199990 has 16 divisors (see below), whose sum is σ = 411552. Its totient is φ = 68544.

The previous prime is 199967. The next prime is 199999. The reversal of 199990 is 99991.

199990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199999) 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, 1359 + ... + 1498.

It is an arithmetic number, because the mean of its divisors is an integer number (25722).

2¹⁹⁹⁹⁹⁰ is an apocalyptic number.

199990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

199990 is an abundant number, since it is smaller than the sum of its proper divisors (211562).

It is a weird number, because it is abundant, but not a pseudoperfect number.

199990 is a wasteful number, since it uses less digits than its factorization.

199990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2871.

The product of its (nonzero) digits is 6561, while the sum is 37.

The square root of 199990 is about 447.2024150203. The cubic root of 199990 is about 58.4793800754.

Subtracting from 199990 its reverse (99991), we obtain a palindrome (99999).

The spelling of 199990 in words is "one hundred ninety-nine thousand, nine hundred ninety".