27771641681 has 16 divisors (see below), whose sum is σ = 31996702080. Its totient is φ = 23611286400.

The previous prime is 27771641603. The next prime is 27771641687. The reversal of 27771641681 is 18614617772.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27771641681 is a prime.

It is a super-2 number, since 2×27771641681² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (27771641687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1236530 + ... + 1258788.

It is an arithmetic number, because the mean of its divisors is an integer number (1999793880).

Almost surely, 2^27771641681 is an apocalyptic number.

It is an amenable number.

27771641681 is a deficient number, since it is larger than the sum of its proper divisors (4225060399).

27771641681 is a wasteful number, since it uses less digits than its factorization.

27771641681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23704.

The product of its digits is 790272, while the sum is 50.

The spelling of 27771641681 in words is "twenty-seven billion, seven hundred seventy-one million, six hundred forty-one thousand, six hundred eighty-one".