28115688 has 64 divisors (see below), whose sum is σ = 75116160. Its totient is φ = 8738816.

The previous prime is 28115629. The next prime is 28115699. The reversal of 28115688 is 88651182.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55645 + ... + 56147.

It is an arithmetic number, because the mean of its divisors is an integer number (1173690).

Almost surely, 2^28115688 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 28115688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37558080).

28115688 is an abundant number, since it is smaller than the sum of its proper divisors (47000472).

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

28115688 is a wasteful number, since it uses less digits than its factorization.

28115688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666 (or 662 counting only the distinct ones).

The product of its digits is 30720, while the sum is 39.

The square root of 28115688 is about 5302.4228424372. The cubic root of 28115688 is about 304.0765331316.

The spelling of 28115688 in words is "twenty-eight million, one hundred fifteen thousand, six hundred eighty-eight".