27808966657 has 4 divisors (see below), whose sum is σ = 27903878100. Its totient is φ = 27714055216.

The previous prime is 27808966631. The next prime is 27808966663. The reversal of 27808966657 is 75666980872.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13464353296 + 14344613361 = 116036^2 + 119769^2 .

It is a cyclic number.

It is not a de Polignac number, because 27808966657 - 2⁷ = 27808966529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27808966667) 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, 47455282 + ... + 47455867.

It is an arithmetic number, because the mean of its divisors is an integer number (6975969525).

Almost surely, 2^27808966657 is an apocalyptic number.

It is an amenable number.

27808966657 is a deficient number, since it is larger than the sum of its proper divisors (94911443).

27808966657 is an equidigital number, since it uses as much as digits as its factorization.

27808966657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94911442.

The product of its (nonzero) digits is 60963840, while the sum is 64.

The spelling of 27808966657 in words is "twenty-seven billion, eight hundred eight million, nine hundred sixty-six thousand, six hundred fifty-seven".