666730987992 has 128 divisors (see below), whose sum is σ = 1880252985600. Its totient is φ = 218859024384.

The previous prime is 666730987919. The next prime is 666730987999. The reversal of 666730987992 is 299789037666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 666730987992.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666730987999) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 72254083 + ... + 72263309.

It is an arithmetic number, because the mean of its divisors is an integer number (14689476450).

Almost surely, 2^666730987992 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 666730987992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940126492800).

666730987992 is an abundant number, since it is smaller than the sum of its proper divisors (1213521997608).

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

666730987992 is a wasteful number, since it uses less digits than its factorization.

666730987992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14302 (or 14292 counting only the distinct ones).

The product of its (nonzero) digits is 370355328, while the sum is 72.

The spelling of 666730987992 in words is "six hundred sixty-six billion, seven hundred thirty million, nine hundred eighty-seven thousand, nine hundred ninety-two".