398084640 has 144 divisors (see below), whose sum is σ = 1297223424. Its totient is φ = 102612480.

The previous prime is 398084639. The next prime is 398084651. The reversal of 398084640 is 46480893.

It is a junction number, because it is equal to n+sod(n) for n = 398084592 and 398084601.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 460849 + ... + 461711.

It is an arithmetic number, because the mean of its divisors is an integer number (9008496).

Almost surely, 2^398084640 is an apocalyptic number.

398084640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398084640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (648611712).

398084640 is an abundant number, since it is smaller than the sum of its proper divisors (899138784).

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

398084640 is a wasteful number, since it uses less digits than its factorization.

398084640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 943 (or 904 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The square root of 398084640 is about 19952.0585404113. The cubic root of 398084640 is about 735.6283765049.

The spelling of 398084640 in words is "three hundred ninety-eight million, eighty-four thousand, six hundred forty".