398978688 has 32 divisors (see below), whose sum is σ = 1059788160. Its totient is φ = 132992768.

The previous prime is 398978687. The next prime is 398978719. The reversal of 398978688 is 886879893.

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (398978683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 519120 + ... + 519887.

It is an arithmetic number, because the mean of its divisors is an integer number (33118380).

Almost surely, 2^398978688 is an apocalyptic number.

It is an amenable number.

398978688 is an abundant number, since it is smaller than the sum of its proper divisors (660809472).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398978688 is a wasteful number, since it uses less digits than its factorization.

398978688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1039024 (or 1039012 counting only the distinct ones).

The product of its digits is 41803776, while the sum is 66.

The square root of 398978688 is about 19974.4508810630. The cubic root of 398978688 is about 736.1786743272.

The spelling of 398978688 in words is "three hundred ninety-eight million, nine hundred seventy-eight thousand, six hundred eighty-eight".