66165665607 has 12 divisors (see below), whose sum is σ = 100602766680. Its totient is φ = 41788841328.

The previous prime is 66165665603. The next prime is 66165665653. The reversal of 66165665607 is 70656656166.

66165665607 is a `hidden beast` number, since 6 + 6 + 16 + 5 + 66 + 560 + 7 = 666.

It is not a de Polignac number, because 66165665607 - 2² = 66165665603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66165665603) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 193466688 + ... + 193467029.

It is an arithmetic number, because the mean of its divisors is an integer number (8383563890).

Almost surely, 2^66165665607 is an apocalyptic number.

66165665607 is a deficient number, since it is larger than the sum of its proper divisors (34437101073).

66165665607 is a wasteful number, since it uses less digits than its factorization.

66165665607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386933742 (or 386933739 counting only the distinct ones).

The product of its (nonzero) digits is 8164800, while the sum is 54.

The spelling of 66165665607 in words is "sixty-six billion, one hundred sixty-five million, six hundred sixty-five thousand, six hundred seven".