28539980 has 24 divisors (see below), whose sum is σ = 68496288. Its totient is φ = 9785088.

The previous prime is 28539967. The next prime is 28539989. The reversal of 28539980 is 8993582.

It is not an unprimeable number, because it can be changed into a prime (28539989) 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, 101789 + ... + 102068.

It is an arithmetic number, because the mean of its divisors is an integer number (2854012).

Almost surely, 2^28539980 is an apocalyptic number.

28539980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28539980 is an abundant number, since it is smaller than the sum of its proper divisors (39956308).

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

28539980 is a wasteful number, since it uses less digits than its factorization.

28539980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203873 (or 203871 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 44.

The square root of 28539980 is about 5342.2822838184. The cubic root of 28539980 is about 305.5985022952.

The spelling of 28539980 in words is "twenty-eight million, five hundred thirty-nine thousand, nine hundred eighty".