28320775457 has 12 divisors (see below), whose sum is σ = 30714834924. Its totient is φ = 26101370880.

The previous prime is 28320775453. The next prime is 28320775519. The reversal of 28320775457 is 75457702382.

It can be written as a sum of positive squares in 6 ways, for example, as 5880435856 + 22440339601 = 76684^2 + 149801^2 .

It is not a de Polignac number, because 28320775457 - 2² = 28320775453 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28320775453) 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, 22388 + ... + 239045.

It is an arithmetic number, because the mean of its divisors is an integer number (2559569577).

Almost surely, 2^28320775457 is an apocalyptic number.

It is an amenable number.

28320775457 is a deficient number, since it is larger than the sum of its proper divisors (2394059467).

28320775457 is a wasteful number, since it uses less digits than its factorization.

28320775457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262100 (or 262087 counting only the distinct ones).

The product of its (nonzero) digits is 3292800, while the sum is 50.

The spelling of 28320775457 in words is "twenty-eight billion, three hundred twenty million, seven hundred seventy-five thousand, four hundred fifty-seven".