28398919 has 2 divisors, whose sum is σ = 28398920. Its totient is φ = 28398918.

The previous prime is 28398913. The next prime is 28398947. The reversal of 28398919 is 91989382.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28398919 - 2³ = 28398911 is a prime.

It is a super-2 number, since 2×28398919² = 1612997200737122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28398911) 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, 14199459 + 14199460.

It is an arithmetic number, because the mean of its divisors is an integer number (14199460).

Almost surely, 2^28398919 is an apocalyptic number.

28398919 is a deficient number, since it is larger than the sum of its proper divisors (1).

28398919 is an equidigital number, since it uses as much as digits as its factorization.

28398919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 279936, while the sum is 49.

The square root of 28398919 is about 5329.0636138068. The cubic root of 28398919 is about 305.0941893098.

The spelling of 28398919 in words is "twenty-eight million, three hundred ninety-eight thousand, nine hundred nineteen".