66914879920 has 40 divisors (see below), whose sum is σ = 177802396704. Its totient is φ = 22942244352.

The previous prime is 66914879909. The next prime is 66914879921. The reversal of 66914879920 is 2997841966.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (66914879921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59744869 + ... + 59745988.

Almost surely, 2^66914879920 is an apocalyptic number.

It is an amenable number.

66914879920 is an abundant number, since it is smaller than the sum of its proper divisors (110887516784).

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

66914879920 is a wasteful number, since it uses less digits than its factorization.

66914879920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119490877 (or 119490871 counting only the distinct ones).

The product of its (nonzero) digits is 11757312, while the sum is 61.

The spelling of 66914879920 in words is "sixty-six billion, nine hundred fourteen million, eight hundred seventy-nine thousand, nine hundred twenty".