28520789 has 12 divisors (see below), whose sum is σ = 32119500. Its totient is φ = 25291200.

The previous prime is 28520773. The next prime is 28520809. The reversal of 28520789 is 98702582.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 874225 + 27646564 = 935^2 + 5258^2 .

It is not a de Polignac number, because 28520789 - 2⁴ = 28520773 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28520389) 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 11 ways as a sum of consecutive naturals, for example, 2087 + ... + 7835.

It is an arithmetic number, because the mean of its divisors is an integer number (2676625).

Almost surely, 2^28520789 is an apocalyptic number.

It is an amenable number.

28520789 is a deficient number, since it is larger than the sum of its proper divisors (3598711).

28520789 is a wasteful number, since it uses less digits than its factorization.

28520789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5812 (or 5801 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 28520789 is about 5340.4858393221. The cubic root of 28520789 is about 305.5299895646.

The spelling of 28520789 in words is "twenty-eight million, five hundred twenty thousand, seven hundred eighty-nine".