28520805 has 48 divisors (see below), whose sum is σ = 50474880. Its totient is φ = 13723776.

The previous prime is 28520773. The next prime is 28520809. The reversal of 28520805 is 50802582.

It is not a de Polignac number, because 28520805 - 2⁵ = 28520773 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28520809) 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 47 ways as a sum of consecutive naturals, for example, 124431 + ... + 124659.

It is an arithmetic number, because the mean of its divisors is an integer number (1051560).

Almost surely, 2^28520805 is an apocalyptic number.

It is an amenable number.

28520805 is a deficient number, since it is larger than the sum of its proper divisors (21954075).

28520805 is a wasteful number, since it uses less digits than its factorization.

28520805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298 (or 279 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 30.

The square root of 28520805 is about 5340.4873373130. The cubic root of 28520805 is about 305.5300466982.

The spelling of 28520805 in words is "twenty-eight million, five hundred twenty thousand, eight hundred five".