27685640893 has 2 divisors, whose sum is σ = 27685640894. Its totient is φ = 27685640892.

The previous prime is 27685640863. The next prime is 27685640897. The reversal of 27685640893 is 39804658672.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27477040644 + 208600249 = 165762^2 + 14443^2 .

It is a cyclic number.

It is not a de Polignac number, because 27685640893 - 2⁵ = 27685640861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27685640897) by changing a digit.

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 as a sum of consecutive naturals, namely, 13842820446 + 13842820447.

It is an arithmetic number, because the mean of its divisors is an integer number (13842820447).

Almost surely, 2^27685640893 is an apocalyptic number.

It is an amenable number.

27685640893 is a deficient number, since it is larger than the sum of its proper divisors (1).

27685640893 is an equidigital number, since it uses as much as digits as its factorization.

27685640893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17418240, while the sum is 58.

The spelling of 27685640893 in words is "twenty-seven billion, six hundred eighty-five million, six hundred forty thousand, eight hundred ninety-three".