28320191 has 2 divisors, whose sum is σ = 28320192. Its totient is φ = 28320190.

The previous prime is 28320119. The next prime is 28320197. The reversal of 28320191 is 19102382.

Together with previous prime (28320119) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28320191 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28320191.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28320197) 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 as a sum of consecutive naturals, namely, 14160095 + 14160096.

It is an arithmetic number, because the mean of its divisors is an integer number (14160096).

Almost surely, 2^28320191 is an apocalyptic number.

28320191 is a deficient number, since it is larger than the sum of its proper divisors (1).

28320191 is an equidigital number, since it uses as much as digits as its factorization.

28320191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 28320191 is about 5321.6718237787. The cubic root of 28320191 is about 304.8119991637.

The spelling of 28320191 in words is "twenty-eight million, three hundred twenty thousand, one hundred ninety-one".