399408 has 40 divisors (see below), whose sum is σ = 1057968. Its totient is φ = 129792.

The previous prime is 399403. The next prime is 399409. The reversal of 399408 is 804993.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (399401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2466 + ... + 2622.

2³⁹⁹⁴⁰⁸ 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 399408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (528984).

399408 is an abundant number, since it is smaller than the sum of its proper divisors (658560).

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

399408 is a wasteful number, since it uses less digits than its factorization.

399408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221 (or 215 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 399408 is about 631.9873416454. The cubic root of 399408 is about 73.6442629150.

The spelling of 399408 in words is "three hundred ninety-nine thousand, four hundred eight".