28875565640 has 64 divisors (see below), whose sum is σ = 67302835200. Its totient is φ = 11136600832.

The previous prime is 28875565637. The next prime is 28875565651. The reversal of 28875565640 is 4656557882.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 845129 + ... + 878631.

It is an arithmetic number, because the mean of its divisors is an integer number (1051606800).

Almost surely, 2^28875565640 is an apocalyptic number.

28875565640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28875565640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33651417600).

28875565640 is an abundant number, since it is smaller than the sum of its proper divisors (38427269560).

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

28875565640 is a wasteful number, since it uses less digits than its factorization.

28875565640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34286 (or 34282 counting only the distinct ones).

The product of its (nonzero) digits is 16128000, while the sum is 56.

The spelling of 28875565640 in words is "twenty-eight billion, eight hundred seventy-five million, five hundred sixty-five thousand, six hundred forty".