66651066566 has 16 divisors (see below), whose sum is σ = 114329846304. Its totient is φ = 28547024064.

The previous prime is 66651066551. The next prime is 66651066569. The reversal of 66651066566 is 66566015666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66651066569) 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 7 ways as a sum of consecutive naturals, for example, 1453175 + ... + 1498338.

It is an arithmetic number, because the mean of its divisors is an integer number (7145615394).

Almost surely, 2^66651066566 is an apocalyptic number.

66651066566 is a deficient number, since it is larger than the sum of its proper divisors (47678779738).

66651066566 is a wasteful number, since it uses less digits than its factorization.

66651066566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2953135.

The product of its (nonzero) digits is 6998400, while the sum is 53.

The spelling of 66651066566 in words is "sixty-six billion, six hundred fifty-one million, sixty-six thousand, five hundred sixty-six".