66667580009856 has 288 divisors, whose sum is σ = 224122027264200. Its totient is φ = 18966125703168.

The previous prime is 66667580009851. The next prime is 66667580009867. The reversal of 66667580009856 is 65890008576666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66667580009851) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 10617955 + ... + 15686813.

Almost surely, 2^{66667580009856} 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 66667580009856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112061013632100).

66667580009856 is an abundant number, since it is smaller than the sum of its proper divisors (157454447254344).

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

66667580009856 is a wasteful number, since it uses less digits than its factorization.

66667580009856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5069126 (or 5069104 counting only the distinct ones).

The product of its (nonzero) digits is 783820800, while the sum is 72.

The spelling of 66667580009856 in words is "sixty-six trillion, six hundred sixty-seven billion, five hundred eighty million, nine thousand, eight hundred fifty-six".