198831809 has 8 divisors (see below), whose sum is σ = 217021728. Its totient is φ = 180660960.

The previous prime is 198831767. The next prime is 198831823. The reversal of 198831809 is 908138891.

It is a happy number.

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 198831809 - 2¹⁶ = 198766273 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (198831869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25334 + ... + 32240.

It is an arithmetic number, because the mean of its divisors is an integer number (27127716).

Almost surely, 2^198831809 is an apocalyptic number.

It is an amenable number.

198831809 is a deficient number, since it is larger than the sum of its proper divisors (18189919).

198831809 is a wasteful number, since it uses less digits than its factorization.

198831809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9535.

The product of its (nonzero) digits is 124416, while the sum is 47.

The square root of 198831809 is about 14100.7733475863. The cubic root of 198831809 is about 583.6627198412.

The spelling of 198831809 in words is "one hundred ninety-eight million, eight hundred thirty-one thousand, eight hundred nine".