399820320 has 96 divisors (see below), whose sum is σ = 1399386240. Its totient is φ = 106617600.

The previous prime is 399820301. The next prime is 399820327. The reversal of 399820320 is 23028993.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (399820327) 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 15 ways as a sum of consecutive naturals, for example, 41956 + ... + 50595.

It is an arithmetic number, because the mean of its divisors is an integer number (14576940).

Almost surely, 2^399820320 is an apocalyptic number.

399820320 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

399820320 is an abundant number, since it is smaller than the sum of its proper divisors (999565920).

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

399820320 is a wasteful number, since it uses less digits than its factorization.

399820320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92575 (or 92561 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 399820320 is about 19995.5074954351. The cubic root of 399820320 is about 736.6959587414.

The spelling of 399820320 in words is "three hundred ninety-nine million, eight hundred twenty thousand, three hundred twenty".