6659999566 has 16 divisors (see below), whose sum is σ = 10900734768. Its totient is φ = 3026563200.

The previous prime is 6659999539. The next prime is 6659999651.

6659999566 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 6659999495 and 6659999504.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 67156 + ... + 133528.

It is an arithmetic number, because the mean of its divisors is an integer number (681295923).

Almost surely, 2^6659999566 is an apocalyptic number.

6659999566 is a deficient number, since it is larger than the sum of its proper divisors (4240735202).

6659999566 is a wasteful number, since it uses less digits than its factorization.

6659999566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70947.

The product of its digits is 212576400, while the sum is 70.

The square root of 6659999566 is about 81608.8203933864. The cubic root of 6659999566 is about 1881.4444503059. Note that the first 4 decimals are identical.

The spelling of 6659999566 in words is "six billion, six hundred fifty-nine million, nine hundred ninety-nine thousand, five hundred sixty-six".