28388625 has 16 divisors (see below), whose sum is σ = 47239296. Its totient is φ = 15140400.

The previous prime is 28388621. The next prime is 28388627. The reversal of 28388625 is 52688382.

It is not a de Polignac number, because 28388625 - 2² = 28388621 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28388621) by changing a digit.

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, 37477 + ... + 38226.

It is an arithmetic number, because the mean of its divisors is an integer number (2952456).

Almost surely, 2^28388625 is an apocalyptic number.

28388625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28388625 is a deficient number, since it is larger than the sum of its proper divisors (18850671).

28388625 is an equidigital number, since it uses as much as digits as its factorization.

28388625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75721 (or 75711 counting only the distinct ones).

The product of its digits is 184320, while the sum is 42.

The square root of 28388625 is about 5328.0976905458. The cubic root of 28388625 is about 305.0573214847.

The spelling of 28388625 in words is "twenty-eight million, three hundred eighty-eight thousand, six hundred twenty-five".