198905 has 8 divisors (see below), whose sum is σ = 272832. Its totient is φ = 136368.

The previous prime is 198901. The next prime is 198929. The reversal of 198905 is 509891.

198905 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 198905 - 2² = 198901 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (198901) 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, 2807 + ... + 2876.

It is an arithmetic number, because the mean of its divisors is an integer number (34104).

2¹⁹⁸⁹⁰⁵ is an apocalyptic number.

It is an amenable number.

198905 is a deficient number, since it is larger than the sum of its proper divisors (73927).

198905 is an equidigital number, since it uses as much as digits as its factorization.

198905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5695.

The product of its (nonzero) digits is 3240, while the sum is 32.

The square root of 198905 is about 445.9876679909. The cubic root of 198905 is about 58.3734327461.

The spelling of 198905 in words is "one hundred ninety-eight thousand, nine hundred five".