198649209 has 48 divisors (see below), whose sum is σ = 305070080. Its totient is φ = 114760800.

The previous prime is 198649201. The next prime is 198649219. The reversal of 198649209 is 902946891.

It is not a de Polignac number, because 198649209 - 2³ = 198649201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198649201) 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 47 ways as a sum of consecutive naturals, for example, 1429062 + ... + 1429200.

Almost surely, 2^198649209 is an apocalyptic number.

It is an amenable number.

198649209 is a deficient number, since it is larger than the sum of its proper divisors (106420871).

198649209 is a wasteful number, since it uses less digits than its factorization.

198649209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322 (or 311 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 48.

The square root of 198649209 is about 14094.2970381641. The cubic root of 198649209 is about 583.4839934841.

The spelling of 198649209 in words is "one hundred ninety-eight million, six hundred forty-nine thousand, two hundred nine".