15805921128 has 16 divisors (see below), whose sum is σ = 39514802880. Its totient is φ = 5268640368.

The previous prime is 15805921073. The next prime is 15805921133. The reversal of 15805921128 is 82112950851.

It is a self number, because there is not a number n which added to its sum of digits gives 15805921128.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 329290000 + ... + 329290047.

It is an arithmetic number, because the mean of its divisors is an integer number (2469675180).

Almost surely, 2^15805921128 is an apocalyptic number.

It is an amenable number.

15805921128 is an abundant number, since it is smaller than the sum of its proper divisors (23708881752).

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

15805921128 is a wasteful number, since it uses less digits than its factorization.

15805921128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 658580056 (or 658580052 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 42.

The spelling of 15805921128 in words is "fifteen billion, eight hundred five million, nine hundred twenty-one thousand, one hundred twenty-eight".