66599557632 has 120 divisors (see below), whose sum is σ = 192908431716. Its totient is φ = 22119284736.

The previous prime is 66599557613. The next prime is 66599557639. The reversal of 66599557632 is 23675599566.

66599557632 is a `hidden beast` number, since 6 + 6 + 59 + 9 + 5 + 576 + 3 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 48055654656 + 18543902976 = 219216^2 + 136176^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66599557632.

It is not an unprimeable number, because it can be changed into a prime (66599557639) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 1250328 + ... + 1302504.

Almost surely, 2^66599557632 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66599557632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96454215858).

66599557632 is an abundant number, since it is smaller than the sum of its proper divisors (126308874084).

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

66599557632 is a wasteful number, since it uses less digits than its factorization.

66599557632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52478 (or 52459 counting only the distinct ones).

The product of its digits is 91854000, while the sum is 63.

The spelling of 66599557632 in words is "sixty-six billion, five hundred ninety-nine million, five hundred fifty-seven thousand, six hundred thirty-two".