28189867 has 2 divisors, whose sum is σ = 28189868. Its totient is φ = 28189866.

The previous prime is 28189853. The next prime is 28189873. The reversal of 28189867 is 76898182.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28189867 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28189867.

It is not a weakly prime, because it can be changed into another prime (28189877) 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, 14094933 + 14094934.

It is an arithmetic number, because the mean of its divisors is an integer number (14094934).

Almost surely, 2^28189867 is an apocalyptic number.

28189867 is a deficient number, since it is larger than the sum of its proper divisors (1).

28189867 is an equidigital number, since it uses as much as digits as its factorization.

28189867 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 387072, while the sum is 49.

The square root of 28189867 is about 5309.4130560731. The cubic root of 28189867 is about 304.3437183087.

The spelling of 28189867 in words is "twenty-eight million, one hundred eighty-nine thousand, eight hundred sixty-seven".