66181038336 has 648 divisors, whose sum is σ = 239248761024. Its totient is φ = 17871114240.

The previous prime is 66181038331. The next prime is 66181038337. The reversal of 66181038336 is 63383018166.

66181038336 is a `hidden beast` number, since 66 + 181 + 0 + 383 + 36 = 666.

It is a tau number, because it is divible by the number of its divisors (648).

It is a super-2 number, since 2×66181038336² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66181038291 and 66181038300.

It is not an unprimeable number, because it can be changed into a prime (66181038331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 157199406 + ... + 157199826.

Almost surely, 2^66181038336 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 66181038336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119624380512).

66181038336 is an abundant number, since it is smaller than the sum of its proper divisors (173067722688).

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

66181038336 is an equidigital number, since it uses as much as digits as its factorization.

66181038336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 497 (or 452 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The spelling of 66181038336 in words is "sixty-six billion, one hundred eighty-one million, thirty-eight thousand, three hundred thirty-six".