399705408 has 224 divisors, whose sum is σ = 1250899200. Its totient is φ = 124895232.

The previous prime is 399705403. The next prime is 399705409. The reversal of 399705408 is 804507993.

399705408 is a `hidden beast` number, since 39 + 9 + 70 + 540 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399705401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3537160 + ... + 3537272.

Almost surely, 2^399705408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 399705408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (625449600).

399705408 is an abundant number, since it is smaller than the sum of its proper divisors (851193792).

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

399705408 is a wasteful number, since it uses less digits than its factorization.

399705408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246 (or 230 counting only the distinct ones).

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

The square root of 399705408 is about 19992.6338434935. The cubic root of 399705408 is about 736.6253742703.

The spelling of 399705408 in words is "three hundred ninety-nine million, seven hundred five thousand, four hundred eight".