28815580 has 12 divisors (see below), whose sum is σ = 60512760. Its totient is φ = 11526224.

The previous prime is 28815569. The next prime is 28815587. The reversal of 28815580 is 8551882.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28815587) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 720370 + ... + 720409.

It is an arithmetic number, because the mean of its divisors is an integer number (5042730).

Almost surely, 2^28815580 is an apocalyptic number.

28815580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28815580 is an abundant number, since it is smaller than the sum of its proper divisors (31697180).

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

28815580 is a wasteful number, since it uses less digits than its factorization.

28815580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1440788 (or 1440786 counting only the distinct ones).

The product of its (nonzero) digits is 25600, while the sum is 37.

The square root of 28815580 is about 5368.0145305317. The cubic root of 28815580 is about 306.5790366088.

The spelling of 28815580 in words is "twenty-eight million, eight hundred fifteen thousand, five hundred eighty".