66748081474656 has 120 divisors (see below), whose sum is σ = 196317058352184. Its totient is φ = 22247909176320.

The previous prime is 66748081474649. The next prime is 66748081474687. The reversal of 66748081474656 is 65647418084766.

66748081474656 is a `hidden beast` number, since 6 + 6 + 7 + 4 + 80 + 81 + 4 + 7 + 465 + 6 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 39273871 + ... + 40938161.

Almost surely, 2^{66748081474656} is an apocalyptic number.

It is an amenable number.

66748081474656 is an abundant number, since it is smaller than the sum of its proper divisors (129568976877528).

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

66748081474656 is a wasteful number, since it uses less digits than its factorization.

66748081474656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1679786 (or 1679769 counting only the distinct ones).

The product of its (nonzero) digits is 1300561920, while the sum is 72.

The spelling of 66748081474656 in words is "sixty-six trillion, seven hundred forty-eight billion, eighty-one million, four hundred seventy-four thousand, six hundred fifty-six".