28000811 has 4 divisors (see below), whose sum is σ = 28065912. Its totient is φ = 27935712.

The previous prime is 28000799. The next prime is 28000831. The reversal of 28000811 is 11800082.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28000811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28000831) 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, 31901 + ... + 32766.

It is an arithmetic number, because the mean of its divisors is an integer number (7016478).

Almost surely, 2^28000811 is an apocalyptic number.

28000811 is a deficient number, since it is larger than the sum of its proper divisors (65101).

28000811 is an equidigital number, since it uses as much as digits as its factorization.

28000811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65100.

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 28000811 is about 5291.5792538712. The cubic root of 28000811 is about 303.6618289136.

Adding to 28000811 its reverse (11800082), we get a palindrome (39800893).

It can be divided in two parts, 2800081 and 1, that added together give a palindrome (2800082).

The spelling of 28000811 in words is "twenty-eight million, eight hundred eleven", and thus it is an aban number.