28885640 has 64 divisors (see below), whose sum is σ = 75375360. Its totient is φ = 9757440.

The previous prime is 28885627. The next prime is 28885651. The reversal of 28885640 is 4658882.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19154 + ... + 20606.

It is an arithmetic number, because the mean of its divisors is an integer number (1177740).

Almost surely, 2^28885640 is an apocalyptic number.

28885640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28885640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37687680).

28885640 is an abundant number, since it is smaller than the sum of its proper divisors (46489720).

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

28885640 is a wasteful number, since it uses less digits than its factorization.

28885640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1542 (or 1538 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 41.

The square root of 28885640 is about 5374.5362590646. The cubic root of 28885640 is about 306.8272997980.

The spelling of 28885640 in words is "twenty-eight million, eight hundred eighty-five thousand, six hundred forty".