398905722 has 80 divisors (see below), whose sum is σ = 946123200. Its totient is φ = 125619336.

The previous prime is 398905709. The next prime is 398905733. The reversal of 398905722 is 227509893.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1110979 + ... + 1111337.

It is an arithmetic number, because the mean of its divisors is an integer number (11826540).

Almost surely, 2^398905722 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398905722, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (473061600).

398905722 is an abundant number, since it is smaller than the sum of its proper divisors (547217478).

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

398905722 is an equidigital number, since it uses as much as digits as its factorization.

398905722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430 (or 383 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 398905722 is about 19972.6243142958. The cubic root of 398905722 is about 736.1337936609.

The spelling of 398905722 in words is "three hundred ninety-eight million, nine hundred five thousand, seven hundred twenty-two".