28686811 has 6 divisors (see below), whose sum is σ = 29643036. Its totient is φ = 27760500.

The previous prime is 28686809. The next prime is 28686817. The reversal of 28686811 is 11868682.

It is not a de Polignac number, because 28686811 - 2¹ = 28686809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28686817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13965 + ... + 15886.

It is an arithmetic number, because the mean of its divisors is an integer number (4940506).

Almost surely, 2^28686811 is an apocalyptic number.

28686811 is a deficient number, since it is larger than the sum of its proper divisors (956225).

28686811 is an equidigital number, since it uses as much as digits as its factorization.

28686811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29913 (or 29882 counting only the distinct ones).

The product of its digits is 36864, while the sum is 40.

The square root of 28686811 is about 5356.0070014891. The cubic root of 28686811 is about 306.1216818526.

It can be divided in two parts, 2868681 and 1, that added together give a palindrome (2868682).

The spelling of 28686811 in words is "twenty-eight million, six hundred eighty-six thousand, eight hundred eleven".