66380398720 has 64 divisors (see below), whose sum is σ = 160602704640. Its totient is φ = 26232232960.

The previous prime is 66380398717. The next prime is 66380398759. The reversal of 66380398720 is 2789308366.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 571696 + ... + 677935.

It is an arithmetic number, because the mean of its divisors is an integer number (2509417260).

Almost surely, 2^66380398720 is an apocalyptic number.

It is an amenable number.

66380398720 is an abundant number, since it is smaller than the sum of its proper divisors (94222305920).

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

66380398720 is a wasteful number, since it uses less digits than its factorization.

66380398720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1249733 (or 1249721 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 52.

The spelling of 66380398720 in words is "sixty-six billion, three hundred eighty million, three hundred ninety-eight thousand, seven hundred twenty".