28135857 has 4 divisors (see below), whose sum is σ = 37514480. Its totient is φ = 18757236.

The previous prime is 28135853. The next prime is 28135871. The reversal of 28135857 is 75853182.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28135857 - 2² = 28135853 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28135853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4689307 + ... + 4689312.

It is an arithmetic number, because the mean of its divisors is an integer number (9378620).

Almost surely, 2^28135857 is an apocalyptic number.

It is an amenable number.

28135857 is a deficient number, since it is larger than the sum of its proper divisors (9378623).

28135857 is an equidigital number, since it uses as much as digits as its factorization.

28135857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9378622.

The product of its digits is 67200, while the sum is 39.

The square root of 28135857 is about 5304.3243679096. The cubic root of 28135857 is about 304.1492262805.

The spelling of 28135857 in words is "twenty-eight million, one hundred thirty-five thousand, eight hundred fifty-seven".