28320655817 has 4 divisors (see below), whose sum is σ = 28321334736. Its totient is φ = 28319976900.

The previous prime is 28320655801. The next prime is 28320655819. The reversal of 28320655817 is 71855602382.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28320655817 - 2⁴ = 28320655801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28320655819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 272483 + ... + 361784.

It is an arithmetic number, because the mean of its divisors is an integer number (7080333684).

Almost surely, 2^28320655817 is an apocalyptic number.

It is an amenable number.

28320655817 is a deficient number, since it is larger than the sum of its proper divisors (678919).

28320655817 is an equidigital number, since it uses as much as digits as its factorization.

28320655817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 678918.

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

The spelling of 28320655817 in words is "twenty-eight billion, three hundred twenty million, six hundred fifty-five thousand, eight hundred seventeen".