66860744856768 has 392 divisors, whose sum is σ = 207828024645888. Its totient is φ = 21291734711808.

The previous prime is 66860744856727. The next prime is 66860744856827. The reversal of 66860744856768 is 86765844706866.

66860744856768 is a `hidden beast` number, since 6 + 6 + 8 + 6 + 0 + 7 + 4 + 48 + 567 + 6 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 883113571 + ... + 883189277.

Almost surely, 2^{66860744856768} 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 66860744856768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103914012322944).

66860744856768 is an abundant number, since it is smaller than the sum of its proper divisors (140967279789120).

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

66860744856768 is an equidigital number, since it uses as much as digits as its factorization.

66860744856768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76583 (or 76558 counting only the distinct ones).

The product of its (nonzero) digits is 15606743040, while the sum is 81.

The spelling of 66860744856768 in words is "sixty-six trillion, eight hundred sixty billion, seven hundred forty-four million, eight hundred fifty-six thousand, seven hundred sixty-eight".