66685316155776 has 480 divisors, whose sum is σ = 210997526216400. Its totient is φ = 20881759481856.

The previous prime is 66685316155751. The next prime is 66685316155789. The reversal of 66685316155776 is 67755161358666.

It is a super-3 number, since 3×66685316155776³ (a number of 42 digits) contains 333 as substring.

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

It is a congruent number.

It is an unprimeable number.

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 59 ways as a sum of consecutive naturals, for example, 411538965 + ... + 411700971.

Almost surely, 2^{66685316155776} 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 66685316155776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105498763108200).

66685316155776 is an abundant number, since it is smaller than the sum of its proper divisors (144312210060624).

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

66685316155776 is a wasteful number, since it uses less digits than its factorization.

66685316155776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162136 (or 162078 counting only the distinct ones).

The product of its digits is 1143072000, while the sum is 72.

The spelling of 66685316155776 in words is "sixty-six trillion, six hundred eighty-five billion, three hundred sixteen million, one hundred fifty-five thousand, seven hundred seventy-six".