28555865 has 16 divisors (see below), whose sum is σ = 38178000. Its totient is φ = 20358912.

The previous prime is 28555843. The next prime is 28555871. The reversal of 28555865 is 56855582.

It can be written as a sum of positive squares in 8 ways, for example, as 635209 + 27920656 = 797^2 + 5284^2 .

It is a cyclic number.

It is not a de Polignac number, because 28555865 - 2⁸ = 28555609 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5690 + ... + 9459.

It is an arithmetic number, because the mean of its divisors is an integer number (2386125).

Almost surely, 2^28555865 is an apocalyptic number.

It is an amenable number.

28555865 is a deficient number, since it is larger than the sum of its proper divisors (9622135).

28555865 is a wasteful number, since it uses less digits than its factorization.

28555865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15196.

The product of its digits is 480000, while the sum is 44.

The square root of 28555865 is about 5343.7688011365. The cubic root of 28555865 is about 305.6551892288.

The spelling of 28555865 in words is "twenty-eight million, five hundred fifty-five thousand, eight hundred sixty-five".