28239588 has 72 divisors (see below), whose sum is σ = 77907648. Its totient is φ = 8572608.

The previous prime is 28239571. The next prime is 28239641. The reversal of 28239588 is 88593282.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38481 + ... + 39207.

Almost surely, 2^28239588 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28239588, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38953824).

28239588 is an abundant number, since it is smaller than the sum of its proper divisors (49668060).

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

28239588 is a wasteful number, since it uses less digits than its factorization.

28239588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 833 (or 828 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 28239588 is about 5314.0933375318. The cubic root of 28239588 is about 304.5225459941.

The spelling of 28239588 in words is "twenty-eight million, two hundred thirty-nine thousand, five hundred eighty-eight".