27129411891 has 20 divisors (see below), whose sum is σ = 40531856904. Its totient is φ = 18083952000.

The previous prime is 27129411887. The next prime is 27129411929. The reversal of 27129411891 is 19811492172.

27129411891 is a `hidden beast` number, since 27 + 129 + 411 + 8 + 91 = 666.

It is not a de Polignac number, because 27129411891 - 2² = 27129411887 is a prime.

It is not an unprimeable number, because it can be changed into a prime (27129411871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 810691 + ... + 843491.

Almost surely, 2^27129411891 is an apocalyptic number.

27129411891 is a deficient number, since it is larger than the sum of its proper divisors (13402445013).

27129411891 is a wasteful number, since it uses less digits than its factorization.

27129411891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43024 (or 43015 counting only the distinct ones).

The product of its digits is 72576, while the sum is 45.

The spelling of 27129411891 in words is "twenty-seven billion, one hundred twenty-nine million, four hundred eleven thousand, eight hundred ninety-one".