199890 has 24 divisors (see below), whose sum is σ = 519948. Its totient is φ = 53280.

The previous prime is 199889. The next prime is 199909. The reversal of 199890 is 98991.

It can be written as a sum of positive squares in 2 ways, for example, as 199809 + 81 = 447^2 + 9^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1021 + ... + 1200.

2¹⁹⁹⁸⁹⁰ is an apocalyptic number.

199890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

199890 is an abundant number, since it is smaller than the sum of its proper divisors (320058).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

199890 is a wasteful number, since it uses less digits than its factorization.

199890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2234 (or 2231 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 36.

The square root of 199890 is about 447.0905948463. The cubic root of 199890 is about 58.4696313997.

It can be divided in two parts, 199 and 890, that added together give a square (1089 = 33²).

The spelling of 199890 in words is "one hundred ninety-nine thousand, eight hundred ninety".