198218818 has 12 divisors (see below), whose sum is σ = 345871782. Its totient is φ = 84950880.

The previous prime is 198218771. The next prime is 198218843. The reversal of 198218818 is 818812891.

It can be written as a sum of positive squares in only one way, i.e., 110103049 + 88115769 = 10493^2 + 9387^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1011223 + ... + 1011418.

Almost surely, 2^198218818 is an apocalyptic number.

198218818 is a deficient number, since it is larger than the sum of its proper divisors (147652964).

198218818 is a wasteful number, since it uses less digits than its factorization.

198218818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2022657 (or 2022650 counting only the distinct ones).

The product of its digits is 73728, while the sum is 46.

The square root of 198218818 is about 14079.0204914973. The cubic root of 198218818 is about 583.0622989776.

The spelling of 198218818 in words is "one hundred ninety-eight million, two hundred eighteen thousand, eight hundred eighteen".