28093885 has 4 divisors (see below), whose sum is σ = 33712668. Its totient is φ = 22475104.

The previous prime is 28093823. The next prime is 28093903. The reversal of 28093885 is 58839082.

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 16662724 + 11431161 = 4082^2 + 3381^2 .

It is a cyclic number.

It is not a de Polignac number, because 28093885 - 2¹³ = 28085693 is a prime.

It is a Duffinian number.

It is a congruent 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, 2809384 + ... + 2809393.

It is an arithmetic number, because the mean of its divisors is an integer number (8428167).

Almost surely, 2^28093885 is an apocalyptic number.

It is an amenable number.

28093885 is a deficient number, since it is larger than the sum of its proper divisors (5618783).

28093885 is an equidigital number, since it uses as much as digits as its factorization.

28093885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5618782.

The product of its (nonzero) digits is 138240, while the sum is 43.

The square root of 28093885 is about 5300.3664967623. The cubic root of 28093885 is about 303.9979116027.

The spelling of 28093885 in words is "twenty-eight million, ninety-three thousand, eight hundred eighty-five".