6663553666 has 16 divisors (see below), whose sum is σ = 12461711040. Its totient is φ = 2596189680.

The previous prime is 6663553643. The next prime is 6663553693.

6663553666 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21634761 + ... + 21635068.

It is an arithmetic number, because the mean of its divisors is an integer number (778856940).

Almost surely, 2^6663553666 is an apocalyptic number.

6663553666 is a deficient number, since it is larger than the sum of its proper divisors (5798157374).

6663553666 is a wasteful number, since it uses less digits than its factorization.

6663553666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43269849.

The product of its digits is 10497600, while the sum is 52.

The square root of 6663553666 is about 81630.5927088613. The cubic root of 6663553666 is about 1881.7790675749.

The spelling of 6663553666 in words is "six billion, six hundred sixty-three million, five hundred fifty-three thousand, six hundred sixty-six".