398779920 has 240 divisors, whose sum is σ = 1669928832. Its totient is φ = 82851840.

The previous prime is 398779883. The next prime is 398779921. The reversal of 398779920 is 29977893.

It is a tau number, because it is divible by the number of its divisors (240).

It is not an unprimeable number, because it can be changed into a prime (398779921) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 51844 + ... + 59036.

Almost surely, 2^398779920 is an apocalyptic number.

398779920 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 398779920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (834964416).

398779920 is an abundant number, since it is smaller than the sum of its proper divisors (1271148912).

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

398779920 is a wasteful number, since it uses less digits than its factorization.

398779920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7230 (or 7221 counting only the distinct ones).

The product of its (nonzero) digits is 1714608, while the sum is 54.

The square root of 398779920 is about 19969.4747051594. The cubic root of 398779920 is about 736.0564012385.

The spelling of 398779920 in words is "three hundred ninety-eight million, seven hundred seventy-nine thousand, nine hundred twenty".