66651600520 has 32 divisors (see below), whose sum is σ = 153156873600. Its totient is φ = 26093391808.

The previous prime is 66651600517. The next prime is 66651600541. The reversal of 66651600520 is 2500615666.

It is a self number, because there is not a number n which added to its sum of digits gives 66651600520.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17724610 + ... + 17728369.

It is an arithmetic number, because the mean of its divisors is an integer number (4786152300).

Almost surely, 2^66651600520 is an apocalyptic number.

It is an amenable number.

66651600520 is an abundant number, since it is smaller than the sum of its proper divisors (86505273080).

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

66651600520 is a wasteful number, since it uses less digits than its factorization.

66651600520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35453037 (or 35453033 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 37.

The spelling of 66651600520 in words is "sixty-six billion, six hundred fifty-one million, six hundred thousand, five hundred twenty".