28189979 has 2 divisors, whose sum is σ = 28189980. Its totient is φ = 28189978.

The previous prime is 28189963. The next prime is 28189981. The reversal of 28189979 is 97998182.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28189979 - 2⁴ = 28189963 is a prime.

Together with 28189981, it forms a pair of twin primes.

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 28189979.

It is not a weakly prime, because it can be changed into another prime (28189279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14094989 + 14094990.

It is an arithmetic number, because the mean of its divisors is an integer number (14094990).

Almost surely, 2^28189979 is an apocalyptic number.

28189979 is a deficient number, since it is larger than the sum of its proper divisors (1).

28189979 is an equidigital number, since it uses as much as digits as its factorization.

28189979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 653184, while the sum is 53.

The square root of 28189979 is about 5309.4236033679. The cubic root of 28189979 is about 304.3441213666.

The spelling of 28189979 in words is "twenty-eight million, one hundred eighty-nine thousand, nine hundred seventy-nine".