66171606656 has 32 divisors (see below), whose sum is σ = 131843347680. Its totient is φ = 33081511680.

The previous prime is 66171606629. The next prime is 66171606661. The reversal of 66171606656 is 65660617166.

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1108451 + ... + 1166621.

It is an arithmetic number, because the mean of its divisors is an integer number (4120104615).

Almost surely, 2^66171606656 is an apocalyptic number.

It is an amenable number.

66171606656 is a deficient number, since it is larger than the sum of its proper divisors (65671741024).

66171606656 is an equidigital number, since it uses as much as digits as its factorization.

66171606656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67072 (or 67060 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 50.

The spelling of 66171606656 in words is "sixty-six billion, one hundred seventy-one million, six hundred six thousand, six hundred fifty-six".