198978664 has 32 divisors (see below), whose sum is σ = 377324640. Its totient is φ = 98366400.

The previous prime is 198978653. The next prime is 198978667. The reversal of 198978664 is 466879891.

198978664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 198978599 and 198978608.

It is not an unprimeable number, because it can be changed into a prime (198978667) 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, 431394 + ... + 431854.

It is an arithmetic number, because the mean of its divisors is an integer number (11791395).

Almost surely, 2^198978664 is an apocalyptic number.

It is an amenable number.

198978664 is a deficient number, since it is larger than the sum of its proper divisors (178345976).

198978664 is a wasteful number, since it uses less digits than its factorization.

198978664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 961 (or 957 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 58.

The square root of 198978664 is about 14105.9797249252. The cubic root of 198978664 is about 583.8063801127.

It can be divided in two parts, 19897 and 8664, that added together give a 4-th power (28561 = 13⁴).

The spelling of 198978664 in words is "one hundred ninety-eight million, nine hundred seventy-eight thousand, six hundred sixty-four".