399394080 has 288 divisors, whose sum is σ = 1471841280. Its totient is φ = 98334720.

The previous prime is 399394067. The next prime is 399394081. The reversal of 399394080 is 80493993.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×399394080² = 319031262278092800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399394081) 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, 1026526 + ... + 1026914.

It is an arithmetic number, because the mean of its divisors is an integer number (5110560).

Almost surely, 2^399394080 is an apocalyptic number.

399394080 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 399394080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (735920640).

399394080 is an abundant number, since it is smaller than the sum of its proper divisors (1072447200).

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

399394080 is a wasteful number, since it uses less digits than its factorization.

399394080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The square root of 399394080 is about 19984.8462591034. The cubic root of 399394080 is about 736.4340736545.

The spelling of 399394080 in words is "three hundred ninety-nine million, three hundred ninety-four thousand, eighty".