66218170788864 has 1056 divisors, whose sum is σ = 220774010184000. Its totient is φ = 19726923202560.

The previous prime is 66218170788863. The next prime is 66218170788911. The reversal of 66218170788864 is 46888707181266.

It is a super-2 number, since 2×66218170788864² (a number of 28 digits) contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 66218170788792 and 66218170788801.

It is not an unprimeable number, because it can be changed into a prime (66218170788863) 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 95 ways as a sum of consecutive naturals, for example, 7483120312 + ... + 7483129160.

Almost surely, 2^{66218170788864} is an apocalyptic number.

66218170788864 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66218170788864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110387005092000).

66218170788864 is an abundant number, since it is smaller than the sum of its proper divisors (154555839395136).

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

66218170788864 is a wasteful number, since it uses less digits than its factorization.

66218170788864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8991 (or 8961 counting only the distinct ones).

The product of its (nonzero) digits is 346816512, while the sum is 72.

The spelling of 66218170788864 in words is "sixty-six trillion, two hundred eighteen billion, one hundred seventy million, seven hundred eighty-eight thousand, eight hundred sixty-four".