66147775680 has 112 divisors (see below), whose sum is σ = 240021953280. Its totient is φ = 15119490048.

The previous prime is 66147775669. The next prime is 66147775709. The reversal of 66147775680 is 8657774166.

It is a tau number, because it is divible by the number of its divisors (112).

It is a self number, because there is not a number n which added to its sum of digits gives 66147775680.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4914990 + ... + 4928429.

Almost surely, 2^66147775680 is an apocalyptic number.

66147775680 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66147775680 is an abundant number, since it is smaller than the sum of its proper divisors (173874177600).

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

66147775680 is a wasteful number, since it uses less digits than its factorization.

66147775680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9843446 (or 9843436 counting only the distinct ones).

The product of its (nonzero) digits is 11854080, while the sum is 57.

The spelling of 66147775680 in words is "sixty-six billion, one hundred forty-seven million, seven hundred seventy-five thousand, six hundred eighty".