66391834688 has 28 divisors (see below), whose sum is σ = 133104518652. Its totient is φ = 32853688320.

The previous prime is 66391834679. The next prime is 66391834693. The reversal of 66391834688 is 88643819366.

It can be written as a sum of positive squares in 2 ways, for example, as 50477507584 + 15914327104 = 224672^2 + 126152^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66391834688.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5341073 + ... + 5353488.

It is an arithmetic number, because the mean of its divisors is an integer number (4753732809).

Almost surely, 2^66391834688 is an apocalyptic number.

It is an amenable number.

66391834688 is an abundant number, since it is smaller than the sum of its proper divisors (66712683964).

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

66391834688 is a wasteful number, since it uses less digits than its factorization.

66391834688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10694670 (or 10694660 counting only the distinct ones).

The product of its digits is 35831808, while the sum is 62.

The spelling of 66391834688 in words is "sixty-six billion, three hundred ninety-one million, eight hundred thirty-four thousand, six hundred eighty-eight".