180181998666 has 128 divisors (see below), whose sum is σ = 446956392960. Its totient is φ = 53511929856.

The previous prime is 180181998641. The next prime is 180181998707. The reversal of 180181998666 is 666899181081.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2004070 + ... + 2092046.

It is an arithmetic number, because the mean of its divisors is an integer number (3491846820).

Almost surely, 2^180181998666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 180181998666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (223478196480).

180181998666 is an abundant number, since it is smaller than the sum of its proper divisors (266774394294).

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

180181998666 is a wasteful number, since it uses less digits than its factorization.

180181998666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88125 (or 88119 counting only the distinct ones).

The product of its (nonzero) digits is 8957952, while the sum is 63.

The spelling of 180181998666 in words is "one hundred eighty billion, one hundred eighty-one million, nine hundred ninety-eight thousand, six hundred sixty-six".