5661656671 has 6 divisors (see below), whose sum is σ = 6223143416. Its totient is φ = 5146960500.

The previous prime is 5661656641. The next prime is 5661656681. The reversal of 5661656671 is 1766561665.

It is not a de Polignac number, because 5661656671 - 2⁹ = 5661656159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5661656641) 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 5 ways as a sum of consecutive naturals, for example, 23395155 + ... + 23395396.

Almost surely, 2^5661656671 is an apocalyptic number.

5661656671 is a deficient number, since it is larger than the sum of its proper divisors (561486745).

5661656671 is a wasteful number, since it uses less digits than its factorization.

5661656671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46790573 (or 46790562 counting only the distinct ones).

The product of its digits is 1360800, while the sum is 49.

The square root of 5661656671 is about 75243.9809619348. The cubic root of 5661656671 is about 1782.3015163226.

The spelling of 5661656671 in words is "five billion, six hundred sixty-one million, six hundred fifty-six thousand, six hundred seventy-one".