198812091 has 16 divisors (see below), whose sum is σ = 272701440. Its totient is φ = 128765280.

The previous prime is 198812077. The next prime is 198812113. The reversal of 198812091 is 190218891.

It is not a de Polignac number, because 198812091 - 2¹⁵ = 198779323 is a prime.

It is not an unprimeable number, because it can be changed into a prime (198812051) 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 15 ways as a sum of consecutive naturals, for example, 20605 + ... + 28673.

It is an arithmetic number, because the mean of its divisors is an integer number (17043840).

Almost surely, 2^198812091 is an apocalyptic number.

198812091 is a deficient number, since it is larger than the sum of its proper divisors (73889349).

198812091 is a wasteful number, since it uses less digits than its factorization.

198812091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8306.

The product of its (nonzero) digits is 10368, while the sum is 39.

The square root of 198812091 is about 14100.0741487412. The cubic root of 198812091 is about 583.6434254067.

The spelling of 198812091 in words is "one hundred ninety-eight million, eight hundred twelve thousand, ninety-one".