28320788693 has 2 divisors, whose sum is σ = 28320788694. Its totient is φ = 28320788692.

The previous prime is 28320788669. The next prime is 28320788711. The reversal of 28320788693 is 39688702382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16760668369 + 11560120324 = 129463^2 + 107518^2 .

It is a cyclic number.

It is not a de Polignac number, because 28320788693 - 2⁸ = 28320788437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28320788623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14160394346 + 14160394347.

It is an arithmetic number, because the mean of its divisors is an integer number (14160394347).

Almost surely, 2^28320788693 is an apocalyptic number.

It is an amenable number.

28320788693 is a deficient number, since it is larger than the sum of its proper divisors (1).

28320788693 is an equidigital number, since it uses as much as digits as its factorization.

28320788693 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6967296, while the sum is 56.

The spelling of 28320788693 in words is "twenty-eight billion, three hundred twenty million, seven hundred eighty-eight thousand, six hundred ninety-three".