28045889 has 4 divisors (see below), whose sum is σ = 28803924. Its totient is φ = 27287856.

The previous prime is 28045879. The next prime is 28045931. The reversal of 28045889 is 98854082.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22165264 + 5880625 = 4708^2 + 2425^2 .

It is a cyclic number.

It is not a de Polignac number, because 28045889 - 2¹⁶ = 27980353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28045819) 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 in 3 ways as a sum of consecutive naturals, for example, 378962 + ... + 379035.

It is an arithmetic number, because the mean of its divisors is an integer number (7200981).

Almost surely, 2^28045889 is an apocalyptic number.

It is an amenable number.

28045889 is a deficient number, since it is larger than the sum of its proper divisors (758035).

28045889 is an equidigital number, since it uses as much as digits as its factorization.

28045889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 758034.

The product of its (nonzero) digits is 184320, while the sum is 44.

The square root of 28045889 is about 5295.8369499070. The cubic root of 28045889 is about 303.8246947782.

The spelling of 28045889 in words is "twenty-eight million, forty-five thousand, eight hundred eighty-nine".