28815564 has 24 divisors (see below), whose sum is σ = 67420080. Its totient is φ = 9578944.

The previous prime is 28815551. The next prime is 28815569. The reversal of 28815564 is 46551882.

It is not an unprimeable number, because it can be changed into a prime (28815569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1582 + ... + 7754.

It is an arithmetic number, because the mean of its divisors is an integer number (2809170).

Almost surely, 2^28815564 is an apocalyptic number.

It is an amenable number.

28815564 is an abundant number, since it is smaller than the sum of its proper divisors (38604516).

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

28815564 is a wasteful number, since it uses less digits than its factorization.

28815564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6569 (or 6567 counting only the distinct ones).

The product of its digits is 76800, while the sum is 39.

The square root of 28815564 is about 5368.0130402226. The cubic root of 28815564 is about 306.5789798656.

The spelling of 28815564 in words is "twenty-eight million, eight hundred fifteen thousand, five hundred sixty-four".