28033640 has 32 divisors (see below), whose sum is σ = 63970560. Its totient is φ = 11054400.

The previous prime is 28033639. The next prime is 28033651. The reversal of 28033640 is 4633082.

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, 2096 + ... + 7775.

It is an arithmetic number, because the mean of its divisors is an integer number (1999080).

Almost surely, 2^28033640 is an apocalyptic number.

28033640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28033640 is an abundant number, since it is smaller than the sum of its proper divisors (35936920).

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

28033640 is a wasteful number, since it uses less digits than its factorization.

28033640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9953 (or 9949 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 28033640 is about 5294.6803491807. The cubic root of 28033640 is about 303.7804566772.

The spelling of 28033640 in words is "twenty-eight million, thirty-three thousand, six hundred forty".