28132688 has 40 divisors (see below), whose sum is σ = 58074408. Its totient is φ = 13156352.

The previous prime is 28132661. The next prime is 28132721. The reversal of 28132688 is 88623182.

It can be written as a sum of positive squares in 4 ways, for example, as 13601344 + 14531344 = 3688^2 + 3812^2 .

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 79520 + ... + 79872.

Almost surely, 2^28132688 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 28132688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29037204).

28132688 is an abundant number, since it is smaller than the sum of its proper divisors (29941720).

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

28132688 is a wasteful number, since it uses less digits than its factorization.

28132688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 671 (or 665 counting only the distinct ones).

The product of its digits is 36864, while the sum is 38.

The square root of 28132688 is about 5304.0256409637. The cubic root of 28132688 is about 304.1378068655.

The spelling of 28132688 in words is "twenty-eight million, one hundred thirty-two thousand, six hundred eighty-eight".