28871604765 has 20 divisors (see below), whose sum is σ = 51755025564. Its totient is φ = 15398188992.

The previous prime is 28871604757. The next prime is 28871604799. The reversal of 28871604765 is 56740617882.

28871604765 is a `hidden beast` number, since 2 + 8 + 8 + 7 + 160 + 476 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 11638741689 + 17232863076 = 107883^2 + 131274^2 .

It is not a de Polignac number, because 28871604765 - 2³ = 28871604757 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 35643552 + ... + 35644361.

Almost surely, 2^28871604765 is an apocalyptic number.

It is an amenable number.

28871604765 is a deficient number, since it is larger than the sum of its proper divisors (22883420799).

28871604765 is an equidigital number, since it uses as much as digits as its factorization.

28871604765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71287930 (or 71287921 counting only the distinct ones).

The product of its (nonzero) digits is 4515840, while the sum is 54.

The spelling of 28871604765 in words is "twenty-eight billion, eight hundred seventy-one million, six hundred four thousand, seven hundred sixty-five".