66646004016 has 80 divisors (see below), whose sum is σ = 175098792960. Its totient is φ = 21839700480.

The previous prime is 66646004011. The next prime is 66646004017. The reversal of 66646004016 is 61040064666.

It is not an unprimeable number, because it can be changed into a prime (66646004011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 845821 + ... + 921251.

It is an arithmetic number, because the mean of its divisors is an integer number (2188734912).

Almost surely, 2^66646004016 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66646004016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87549396480).

66646004016 is an abundant number, since it is smaller than the sum of its proper divisors (108452788944).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66646004016 is a wasteful number, since it uses less digits than its factorization.

66646004016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75754 (or 75748 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 39.

The spelling of 66646004016 in words is "sixty-six billion, six hundred forty-six million, four thousand, sixteen".