28663625 has 8 divisors (see below), whose sum is σ = 35772360. Its totient is φ = 22930800.

The previous prime is 28663603. The next prime is 28663631. The reversal of 28663625 is 52636682.

It can be written as a sum of positive squares in 4 ways, for example, as 8620096 + 20043529 = 2936^2 + 4477^2 .

It is not a de Polignac number, because 28663625 - 2²⁴ = 11886409 is a prime.

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, 114530 + ... + 114779.

It is an arithmetic number, because the mean of its divisors is an integer number (4471545).

Almost surely, 2^28663625 is an apocalyptic number.

28663625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28663625 is a deficient number, since it is larger than the sum of its proper divisors (7108735).

28663625 is an equidigital number, since it uses as much as digits as its factorization.

28663625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229324 (or 229314 counting only the distinct ones).

The product of its digits is 103680, while the sum is 38.

The square root of 28663625 is about 5353.8420783583. The cubic root of 28663625 is about 306.0391857488.

The spelling of 28663625 in words is "twenty-eight million, six hundred sixty-three thousand, six hundred twenty-five".