66542824566 has 256 divisors, whose sum is σ = 166765547520. Its totient is φ = 19573125120.

The previous prime is 66542824511. The next prime is 66542824567.

66542824566 is a `hidden beast` number, since 6 + 6 + 54 + 2 + 8 + 24 + 566 = 666.

66542824566 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66542824567) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 116537061 + ... + 116537631.

It is an arithmetic number, because the mean of its divisors is an integer number (651427920).

Almost surely, 2^66542824566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66542824566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83382773760).

66542824566 is an abundant number, since it is smaller than the sum of its proper divisors (100222722954).

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

66542824566 is a wasteful number, since it uses less digits than its factorization.

66542824566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 756 (or 750 counting only the distinct ones).

The product of its digits is 16588800, while the sum is 54.

The spelling of 66542824566 in words is "sixty-six billion, five hundred forty-two million, eight hundred twenty-four thousand, five hundred sixty-six".