6555666566 has 32 divisors (see below), whose sum is σ = 10318464288. Its totient is φ = 3120848640.

The previous prime is 6555666499. The next prime is 6555666569. The reversal of 6555666566 is 6656665556.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6555666569) 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, 711026 + ... + 720186.

It is an arithmetic number, because the mean of its divisors is an integer number (322452009).

Almost surely, 2^6555666566 is an apocalyptic number.

6555666566 is a deficient number, since it is larger than the sum of its proper divisors (3762797722).

6555666566 is a wasteful number, since it uses less digits than its factorization.

6555666566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9416.

The product of its digits is 29160000, while the sum is 56.

The square root of 6555666566 is about 80967.0708745228. The cubic root of 6555666566 is about 1871.5680334654.

The spelling of 6555666566 in words is "six billion, five hundred fifty-five million, six hundred sixty-six thousand, five hundred sixty-six".