66385373095566 has 512 divisors, whose sum is σ = 182262651863040. Its totient is φ = 17480771481600.

The previous prime is 66385373095553. The next prime is 66385373095567. The reversal of 66385373095566 is 66559037358366.

It is a happy number.

66385373095566 is a `hidden beast` number, since 6 + 6 + 3 + 8 + 5 + 37 + 30 + 9 + 556 + 6 = 666.

It is a super-2 number, since 2×66385373095566² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66385373095494 and 66385373095503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66385373095567) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 80272518445 + ... + 80272519271.

It is an arithmetic number, because the mean of its divisors is an integer number (355981741920).

Almost surely, 2^{66385373095566} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66385373095566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91131325931520).

66385373095566 is an abundant number, since it is smaller than the sum of its proper divisors (115877278767474).

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

66385373095566 is a wasteful number, since it uses less digits than its factorization.

66385373095566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1957 (or 1951 counting only the distinct ones).

The product of its (nonzero) digits is 2204496000, while the sum is 72.

The spelling of 66385373095566 in words is "sixty-six trillion, three hundred eighty-five billion, three hundred seventy-three million, ninety-five thousand, five hundred sixty-six".