27988108961 has 2 divisors, whose sum is σ = 27988108962. Its totient is φ = 27988108960.

The previous prime is 27988108937. The next prime is 27988108991. The reversal of 27988108961 is 16980188972.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26391627025 + 1596481936 = 162455^2 + 39956^2 .

It is a cyclic number.

It is not a de Polignac number, because 27988108961 - 2¹⁰ = 27988107937 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27988108961.

It is not a weakly prime, because it can be changed into another prime (27988108991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13994054480 + 13994054481.

It is an arithmetic number, because the mean of its divisors is an integer number (13994054481).

Almost surely, 2^27988108961 is an apocalyptic number.

It is an amenable number.

27988108961 is a deficient number, since it is larger than the sum of its proper divisors (1).

27988108961 is an equidigital number, since it uses as much as digits as its factorization.

27988108961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3483648, while the sum is 59.

The spelling of 27988108961 in words is "twenty-seven billion, nine hundred eighty-eight million, one hundred eight thousand, nine hundred sixty-one".