28921580788 has 12 divisors (see below), whose sum is σ = 50619818340. Its totient is φ = 14458775552.

The previous prime is 28921580749. The next prime is 28921580813. The reversal of 28921580788 is 88708512982.

It can be written as a sum of positive squares in 2 ways, for example, as 28268369424 + 653211364 = 168132^2 + 25558^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 471181 + ... + 529012.

It is an arithmetic number, because the mean of its divisors is an integer number (4218318195).

Almost surely, 2^28921580788 is an apocalyptic number.

It is an amenable number.

28921580788 is a deficient number, since it is larger than the sum of its proper divisors (21698237552).

28921580788 is a wasteful number, since it uses less digits than its factorization.

28921580788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1007426 (or 1007424 counting only the distinct ones).

The product of its (nonzero) digits is 5160960, while the sum is 58.

The spelling of 28921580788 in words is "twenty-eight billion, nine hundred twenty-one million, five hundred eighty thousand, seven hundred eighty-eight".