28875865 has 8 divisors (see below), whose sum is σ = 34777800. Its totient is φ = 23016192.

The previous prime is 28875857. The next prime is 28875871. The reversal of 28875865 is 56857882.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4313929 + 24561936 = 2077^2 + 4956^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28875865 - 2³ = 28875857 is a prime.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 9040 + ... + 11809.

It is an arithmetic number, because the mean of its divisors is an integer number (4347225).

Almost surely, 2^28875865 is an apocalyptic number.

It is an amenable number.

28875865 is a deficient number, since it is larger than the sum of its proper divisors (5901935).

28875865 is a wasteful number, since it uses less digits than its factorization.

28875865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21131.

The product of its digits is 1075200, while the sum is 49.

The square root of 28875865 is about 5373.6268013326. The cubic root of 28875865 is about 306.7926854217.

The spelling of 28875865 in words is "twenty-eight million, eight hundred seventy-five thousand, eight hundred sixty-five".