28133185 has 4 divisors (see below), whose sum is σ = 33759828. Its totient is φ = 22506544.

The previous prime is 28133177. The next prime is 28133191. The reversal of 28133185 is 58133182.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58133182 = 2 ⋅29066591.

It can be written as a sum of positive squares in 2 ways, for example, as 14205361 + 13927824 = 3769^2 + 3732^2 .

It is a cyclic number.

It is not a de Polignac number, because 28133185 - 2³ = 28133177 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, 2813314 + ... + 2813323.

It is an arithmetic number, because the mean of its divisors is an integer number (8439957).

Almost surely, 2^28133185 is an apocalyptic number.

It is an amenable number.

28133185 is a deficient number, since it is larger than the sum of its proper divisors (5626643).

28133185 is an equidigital number, since it uses as much as digits as its factorization.

28133185 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5626642.

The product of its digits is 5760, while the sum is 31.

The square root of 28133185 is about 5304.0724919631. The cubic root of 28133185 is about 304.1395978497.

The spelling of 28133185 in words is "twenty-eight million, one hundred thirty-three thousand, one hundred eighty-five".