28668781536 has 24 divisors (see below), whose sum is σ = 75255551784. Its totient is φ = 9556260480.

The previous prime is 28668781513. The next prime is 28668781597. The reversal of 28668781536 is 63518786682.

It is a tau number, because it is divible by the number of its divisors (24).

It is a self number, because there is not a number n which added to its sum of digits gives 28668781536.

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, 149316475 + ... + 149316666.

It is an arithmetic number, because the mean of its divisors is an integer number (3135647991).

Almost surely, 2^28668781536 is an apocalyptic number.

It is an amenable number.

28668781536 is an abundant number, since it is smaller than the sum of its proper divisors (46586770248).

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

28668781536 is a wasteful number, since it uses less digits than its factorization.

28668781536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298633154 (or 298633146 counting only the distinct ones).

The product of its digits is 23224320, while the sum is 60.

The spelling of 28668781536 in words is "twenty-eight billion, six hundred sixty-eight million, seven hundred eighty-one thousand, five hundred thirty-six".