666933391872 has 320 divisors, whose sum is σ = 2227917225600. Its totient is φ = 195130736640.

The previous prime is 666933391823. The next prime is 666933391903. The reversal of 666933391872 is 278193339666.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4334238 + ... + 4485474.

It is an arithmetic number, because the mean of its divisors is an integer number (6962241330).

Almost surely, 2^666933391872 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 666933391872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1113958612800).

666933391872 is an abundant number, since it is smaller than the sum of its proper divisors (1560983833728).

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

666933391872 is a wasteful number, since it uses less digits than its factorization.

666933391872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151304 (or 151282 counting only the distinct ones).

The product of its digits is 52907904, while the sum is 63.

The spelling of 666933391872 in words is "six hundred sixty-six billion, nine hundred thirty-three million, three hundred ninety-one thousand, eight hundred seventy-two".