399123424 has 72 divisors (see below), whose sum is σ = 962244360. Its totient is φ = 162038016.

The previous prime is 399123409. The next prime is 399123449. The reversal of 399123424 is 424321993.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23094 + ... + 36490.

It is an arithmetic number, because the mean of its divisors is an integer number (13364505).

Almost surely, 2^399123424 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 399123424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (481122180).

399123424 is an abundant number, since it is smaller than the sum of its proper divisors (563120936).

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

399123424 is a wasteful number, since it uses less digits than its factorization.

399123424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13440 (or 13425 counting only the distinct ones).

The product of its digits is 46656, while the sum is 37.

The square root of 399123424 is about 19978.0735808035. The cubic root of 399123424 is about 736.2676838223.

The spelling of 399123424 in words is "three hundred ninety-nine million, one hundred twenty-three thousand, four hundred twenty-four".