399989990528 has 24 divisors (see below), whose sum is σ = 796869314265. Its totient is φ = 199991417600.

The previous prime is 399989990513. The next prime is 399989990581. The reversal of 399989990528 is 825099989993.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 285318359104 + 114671631424 = 534152^2 + 338632^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=447208.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 7127378 + ... + 7183278.

Almost surely, 2^399989990528 is an apocalyptic number.

It is an amenable number.

399989990528 is a deficient number, since it is larger than the sum of its proper divisors (396879323737).

399989990528 is an frugal number, since it uses more digits than its factorization.

399989990528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111816 (or 55903 counting only the distinct ones).

The product of its (nonzero) digits is 1020366720, while the sum is 80.

The spelling of 399989990528 in words is "three hundred ninety-nine billion, nine hundred eighty-nine million, nine hundred ninety thousand, five hundred twenty-eight".