666604617712 has 120 divisors (see below), whose sum is σ = 1554976256400. Its totient is φ = 275344312320.

The previous prime is 666604617673. The next prime is 666604617727. The reversal of 666604617712 is 217716406666.

It is a super-2 number, since 2×666604617712² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 666604617712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 605239 + ... + 1303657.

It is an arithmetic number, because the mean of its divisors is an integer number (12958135470).

Almost surely, 2^666604617712 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 666604617712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (777488128200).

666604617712 is an abundant number, since it is smaller than the sum of its proper divisors (888371638688).

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

666604617712 is a wasteful number, since it uses less digits than its factorization.

666604617712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698495 (or 698478 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 52.

The spelling of 666604617712 in words is "six hundred sixty-six billion, six hundred four million, six hundred seventeen thousand, seven hundred twelve".