6655555566 has 64 divisors (see below), whose sum is σ = 16509968640. Its totient is φ = 1969924320.

The previous prime is 6655555561. The next prime is 6655555567.

6655555566 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×6655555566² = 88592839784227160712, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6655555561) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 104745 + ... + 155828.

It is an arithmetic number, because the mean of its divisors is an integer number (257968260).

Almost surely, 2^6655555566 is an apocalyptic number.

6655555566 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

6655555566 is an abundant number, since it is smaller than the sum of its proper divisors (9854413074).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6655555566 is a wasteful number, since it uses less digits than its factorization.

6655555566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260638 (or 260632 counting only the distinct ones).

The product of its digits is 20250000, while the sum is 54.

The square root of 6655555566 is about 81581.5884008150. The cubic root of 6655555566 is about 1881.0258817335.

The spelling of 6655555566 in words is "six billion, six hundred fifty-five million, five hundred fifty-five thousand, five hundred sixty-six".