28663385 has 4 divisors (see below), whose sum is σ = 34396068. Its totient is φ = 22930704.

The previous prime is 28663367. The next prime is 28663409. The reversal of 28663385 is 58336682.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5053504 + 23609881 = 2248^2 + 4859^2 .

It is a cyclic number.

It is not a de Polignac number, because 28663385 - 2²⁴ = 11886169 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2866334 + ... + 2866343.

It is an arithmetic number, because the mean of its divisors is an integer number (8599017).

Almost surely, 2^28663385 is an apocalyptic number.

It is an amenable number.

28663385 is a deficient number, since it is larger than the sum of its proper divisors (5732683).

28663385 is an equidigital number, since it uses as much as digits as its factorization.

28663385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5732682.

The product of its digits is 207360, while the sum is 41.

The square root of 28663385 is about 5353.8196645012. The cubic root of 28663385 is about 306.0383315930.

The spelling of 28663385 in words is "twenty-eight million, six hundred sixty-three thousand, three hundred eighty-five".