399840916428 has 18 divisors (see below), whose sum is σ = 1010708983284. Its totient is φ = 133280305464.

The previous prime is 399840916399. The next prime is 399840916441. The reversal of 399840916428 is 824619048993.

399840916428 is a `hidden beast` number, since 39 + 98 + 4 + 0 + 91 + 6 + 428 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5553346026 + ... + 5553346097.

Almost surely, 2^399840916428 is an apocalyptic number.

It is an amenable number.

399840916428 is an abundant number, since it is smaller than the sum of its proper divisors (610868066856).

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

399840916428 is a wasteful number, since it uses less digits than its factorization.

399840916428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11106692133 (or 11106692128 counting only the distinct ones).

The product of its (nonzero) digits is 26873856, while the sum is 63.

The spelling of 399840916428 in words is "three hundred ninety-nine billion, eight hundred forty million, nine hundred sixteen thousand, four hundred twenty-eight".