398438947928 has 256 divisors, whose sum is σ = 922602700800. Its totient is φ = 157743936000.

The previous prime is 398438947909. The next prime is 398438947931. The reversal of 398438947928 is 829749834893.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 631440173 + ... + 631440803.

It is an arithmetic number, because the mean of its divisors is an integer number (3603916800).

Almost surely, 2^398438947928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398438947928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (461301350400).

398438947928 is an abundant number, since it is smaller than the sum of its proper divisors (524163752872).

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

398438947928 is a wasteful number, since it uses less digits than its factorization.

398438947928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 902 (or 898 counting only the distinct ones).

The product of its digits is 752467968, while the sum is 74.

The spelling of 398438947928 in words is "three hundred ninety-eight billion, four hundred thirty-eight million, nine hundred forty-seven thousand, nine hundred twenty-eight".