399916728 has 48 divisors (see below), whose sum is σ = 1120462200. Its totient is φ = 128708160.

The previous prime is 399916697. The next prime is 399916729. The reversal of 399916728 is 827619993.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399916729) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 93678 + ... + 97853.

Almost surely, 2^399916728 is an apocalyptic number.

It is an amenable number.

399916728 is an abundant number, since it is smaller than the sum of its proper divisors (720545472).

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

399916728 is a wasteful number, since it uses less digits than its factorization.

399916728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191572 (or 191565 counting only the distinct ones).

The product of its digits is 1469664, while the sum is 54.

The square root of 399916728 is about 19997.9180916414. The cubic root of 399916728 is about 736.7551667345.

The spelling of 399916728 in words is "three hundred ninety-nine million, nine hundred sixteen thousand, seven hundred twenty-eight".