66171646658 has 16 divisors (see below), whose sum is σ = 106901907840. Its totient is φ = 30538117776.

The previous prime is 66171646621. The next prime is 66171646669. The reversal of 66171646658 is 85664617166.

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, 214241 + ... + 422187.

It is an arithmetic number, because the mean of its divisors is an integer number (6681369240).

Almost surely, 2^66171646658 is an apocalyptic number.

66171646658 is a deficient number, since it is larger than the sum of its proper divisors (40730261182).

66171646658 is a wasteful number, since it uses less digits than its factorization.

66171646658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220201.

The product of its digits is 8709120, while the sum is 56.

The spelling of 66171646658 in words is "sixty-six billion, one hundred seventy-one million, six hundred forty-six thousand, six hundred fifty-eight".