66216504672 has 336 divisors, whose sum is σ = 205453221120. Its totient is φ = 20957688576.

The previous prime is 66216504661. The next prime is 66216504677. The reversal of 66216504672 is 27640561266.

66216504672 is a `hidden beast` number, since 6 + 62 + 16 + 504 + 6 + 72 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66216504677) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 89602479 + ... + 89603217.

It is an arithmetic number, because the mean of its divisors is an integer number (611467920).

Almost surely, 2^66216504672 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 66216504672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102726610560).

66216504672 is an abundant number, since it is smaller than the sum of its proper divisors (139236716448).

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

66216504672 is a wasteful number, since it uses less digits than its factorization.

66216504672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 957 (or 934 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 66216504672 in words is "sixty-six billion, two hundred sixteen million, five hundred four thousand, six hundred seventy-two".