28045439 has 4 divisors (see below), whose sum is σ = 28123920. Its totient is φ = 27966960.

The previous prime is 28045403. The next prime is 28045447. The reversal of 28045439 is 93454082.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28045439 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28045399 and 28045408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28045469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38702 + ... + 39419.

It is an arithmetic number, because the mean of its divisors is an integer number (7030980).

Almost surely, 2^28045439 is an apocalyptic number.

28045439 is a deficient number, since it is larger than the sum of its proper divisors (78481).

28045439 is an equidigital number, since it uses as much as digits as its factorization.

28045439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78480.

The product of its (nonzero) digits is 34560, while the sum is 35.

The square root of 28045439 is about 5295.7944635342. The cubic root of 28045439 is about 303.8230698004.

The spelling of 28045439 in words is "twenty-eight million, forty-five thousand, four hundred thirty-nine".