66520718808 has 64 divisors (see below), whose sum is σ = 166796928000. Its totient is φ = 22107645312.

The previous prime is 66520718767. The next prime is 66520718813. The reversal of 66520718808 is 80881702566.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19185091 + ... + 19188557.

It is an arithmetic number, because the mean of its divisors is an integer number (2606202000).

Almost surely, 2^66520718808 is an apocalyptic number.

It is an amenable number.

66520718808 is an abundant number, since it is smaller than the sum of its proper divisors (100276209192).

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

66520718808 is a wasteful number, since it uses less digits than its factorization.

66520718808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5624 (or 5620 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 51.

The spelling of 66520718808 in words is "sixty-six billion, five hundred twenty million, seven hundred eighteen thousand, eight hundred eight".