66309680 has 20 divisors (see below), whose sum is σ = 154170192. Its totient is φ = 26523840.

The previous prime is 66309679. The next prime is 66309697. The reversal of 66309680 is 8690366.

It is a happy number.

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

It is a zygodrome in base 2.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 414356 + ... + 414515.

Almost surely, 2^66309680 is an apocalyptic number.

It is an amenable number.

66309680 is an abundant number, since it is smaller than the sum of its proper divisors (87860512).

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

66309680 is a wasteful number, since it uses less digits than its factorization.

66309680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 828884 (or 828878 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 66309680 is about 8143.0755860424. The cubic root of 66309680 is about 404.7550823214.

The spelling of 66309680 in words is "sixty-six million, three hundred nine thousand, six hundred eighty".