28165857 has 4 divisors (see below), whose sum is σ = 37554480. Its totient is φ = 18777236.

The previous prime is 28165799. The next prime is 28165861. The reversal of 28165857 is 75856182.

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 a cyclic number.

It is not a de Polignac number, because 28165857 - 2²² = 23971553 is a prime.

It is a super-3 number, since 3×28165857³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (28165867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4694307 + ... + 4694312.

It is an arithmetic number, because the mean of its divisors is an integer number (9388620).

Almost surely, 2^28165857 is an apocalyptic number.

It is an amenable number.

28165857 is a deficient number, since it is larger than the sum of its proper divisors (9388623).

28165857 is an equidigital number, since it uses as much as digits as its factorization.

28165857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9388622.

The product of its digits is 134400, while the sum is 42.

The square root of 28165857 is about 5307.1514958591. The cubic root of 28165857 is about 304.2572881000.

The spelling of 28165857 in words is "twenty-eight million, one hundred sixty-five thousand, eight hundred fifty-seven".