27747707661 has 12 divisors (see below), whose sum is σ = 41012116288. Its totient is φ = 18068274504.

The previous prime is 27747707651. The next prime is 27747707681. The reversal of 27747707661 is 16670774772.

It is a happy number.

It is not a de Polignac number, because 27747707661 - 2⁹ = 27747707149 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 27747707598 and 27747707607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27747707651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35849365 + ... + 35850138.

Almost surely, 2^27747707661 is an apocalyptic number.

It is an amenable number.

27747707661 is a deficient number, since it is larger than the sum of its proper divisors (13264408627).

27747707661 is a wasteful number, since it uses less digits than its factorization.

27747707661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71699552 (or 71699549 counting only the distinct ones).

The product of its (nonzero) digits is 4840416, while the sum is 54.

The spelling of 27747707661 in words is "twenty-seven billion, seven hundred forty-seven million, seven hundred seven thousand, six hundred sixty-one".