28555484375809 has 2 divisors, whose sum is σ = 28555484375810. Its totient is φ = 28555484375808.

The previous prime is 28555484375807. The next prime is 28555484375819. The reversal of 28555484375809 is 90857348455582.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17764075415025 + 10791408960784 = 4214745^2 + 3285028^2 .

It is a cyclic number.

It is not a de Polignac number, because 28555484375809 - 2¹ = 28555484375807 is a prime.

Together with 28555484375807, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28555484375807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14277742187904 + 14277742187905.

It is an arithmetic number, because the mean of its divisors is an integer number (14277742187905).

Almost surely, 2^{28555484375809} is an apocalyptic number.

It is an amenable number.

28555484375809 is a deficient number, since it is larger than the sum of its proper divisors (1).

28555484375809 is an equidigital number, since it uses as much as digits as its factorization.

28555484375809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1935360000, while the sum is 73.

The spelling of 28555484375809 in words is "twenty-eight trillion, five hundred fifty-five billion, four hundred eighty-four million, three hundred seventy-five thousand, eight hundred nine".