28688111 has 2 divisors, whose sum is σ = 28688112. Its totient is φ = 28688110.

The previous prime is 28688089. The next prime is 28688123. The reversal of 28688111 is 11188682.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28688111 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28688711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14344055 + 14344056.

It is an arithmetic number, because the mean of its divisors is an integer number (14344056).

Almost surely, 2^28688111 is an apocalyptic number.

28688111 is a deficient number, since it is larger than the sum of its proper divisors (1).

28688111 is an equidigital number, since it uses as much as digits as its factorization.

28688111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6144, while the sum is 35.

The square root of 28688111 is about 5356.1283591789. The cubic root of 28688111 is about 306.1263059541.

The spelling of 28688111 in words is "twenty-eight million, six hundred eighty-eight thousand, one hundred eleven".