28865811 has 16 divisors (see below), whose sum is σ = 42070784. Its totient is φ = 17496864.

The previous prime is 28865803. The next prime is 28865821. The reversal of 28865811 is 11856882.

It is not a de Polignac number, because 28865811 - 2³ = 28865803 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28865811.

It is not an unprimeable number, because it can be changed into a prime (28865801) 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 15 ways as a sum of consecutive naturals, for example, 2911 + ... + 8136.

It is an arithmetic number, because the mean of its divisors is an integer number (2629424).

Almost surely, 2^28865811 is an apocalyptic number.

28865811 is a deficient number, since it is larger than the sum of its proper divisors (13204973).

28865811 is a wasteful number, since it uses less digits than its factorization.

28865811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11130.

The product of its digits is 30720, while the sum is 39.

The square root of 28865811 is about 5372.6912250752. The cubic root of 28865811 is about 306.7570749247.

The spelling of 28865811 in words is "twenty-eight million, eight hundred sixty-five thousand, eight hundred eleven".