66445916080 has 20 divisors (see below), whose sum is σ = 154486755072. Its totient is φ = 26578366400.

The previous prime is 66445916071. The next prime is 66445916081. The reversal of 66445916080 is 8061954466.

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (66445916081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 415286896 + ... + 415287055.

Almost surely, 2^66445916080 is an apocalyptic number.

It is an amenable number.

66445916080 is an abundant number, since it is smaller than the sum of its proper divisors (88040838992).

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

66445916080 is a wasteful number, since it uses less digits than its factorization.

66445916080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 830573964 (or 830573958 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 49.

The spelling of 66445916080 in words is "sixty-six billion, four hundred forty-five million, nine hundred sixteen thousand, eighty".