28091648 has 72 divisors (see below), whose sum is σ = 63184128. Its totient is φ = 12367872.

The previous prime is 28091629. The next prime is 28091663. The reversal of 28091648 is 84619082.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76361 + ... + 76727.

Almost surely, 2^28091648 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 28091648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31592064).

28091648 is an abundant number, since it is smaller than the sum of its proper divisors (35092480).

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

28091648 is a wasteful number, since it uses less digits than its factorization.

28091648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419 (or 405 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 28091648 is about 5300.1554694179. The cubic root of 28091648 is about 303.9898426892.

The spelling of 28091648 in words is "twenty-eight million, ninety-one thousand, six hundred forty-eight".