27771641687 has 2 divisors, whose sum is σ = 27771641688. Its totient is φ = 27771641686.

The previous prime is 27771641603. The next prime is 27771641699. The reversal of 27771641687 is 78614617772.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27771641687 - 2³² = 23476674391 is a prime.

It is a super-3 number, since 3×27771641687³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27771641087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13885820843 + 13885820844.

It is an arithmetic number, because the mean of its divisors is an integer number (13885820844).

Almost surely, 2^27771641687 is an apocalyptic number.

27771641687 is a deficient number, since it is larger than the sum of its proper divisors (1).

27771641687 is an equidigital number, since it uses as much as digits as its factorization.

27771641687 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5531904, while the sum is 56.

The spelling of 27771641687 in words is "twenty-seven billion, seven hundred seventy-one million, six hundred forty-one thousand, six hundred eighty-seven".