28500807665 has 12 divisors (see below), whose sum is σ = 37592801652. Its totient is φ = 20727859680.

The previous prime is 28500807641. The next prime is 28500807667. The reversal of 28500807665 is 56670800582.

It can be written as a sum of positive squares in 2 ways, for example, as 10467540721 + 18033266944 = 102311^2 + 134288^2 .

It is not a de Polignac number, because 28500807665 - 2⁸ = 28500807409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28500807667) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23553782 + ... + 23554991.

It is an arithmetic number, because the mean of its divisors is an integer number (3132733471).

Almost surely, 2^28500807665 is an apocalyptic number.

It is an amenable number.

28500807665 is a deficient number, since it is larger than the sum of its proper divisors (9091993987).

28500807665 is a wasteful number, since it uses less digits than its factorization.

28500807665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47108800 (or 47108789 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 47.

The spelling of 28500807665 in words is "twenty-eight billion, five hundred million, eight hundred seven thousand, six hundred sixty-five".