399942408 has 128 divisors (see below), whose sum is σ = 1107025920. Its totient is φ = 119854080.

The previous prime is 399942401. The next prime is 399942443. The reversal of 399942408 is 804249993.

It is not an unprimeable number, because it can be changed into a prime (399942401) 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, 1302591 + ... + 1302897.

It is an arithmetic number, because the mean of its divisors is an integer number (8648640).

Almost surely, 2^399942408 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 399942408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (553512960).

399942408 is an abundant number, since it is smaller than the sum of its proper divisors (707083512).

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

399942408 is a wasteful number, since it uses less digits than its factorization.

399942408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 467 (or 463 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 48.

The square root of 399942408 is about 19998.5601481707. The cubic root of 399942408 is about 736.7709362405.

The spelling of 399942408 in words is "three hundred ninety-nine million, nine hundred forty-two thousand, four hundred eight".