66641983660 has 96 divisors (see below), whose sum is σ = 161075174400. Its totient is φ = 22687112448.

The previous prime is 66641983621. The next prime is 66641983663. The reversal of 66641983660 is 6638914666.

It is a super-2 number, since 2×66641983660² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66641983663) 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 31 ways as a sum of consecutive naturals, for example, 15237234 + ... + 15241606.

It is an arithmetic number, because the mean of its divisors is an integer number (1677866400).

Almost surely, 2^66641983660 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 66641983660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80537587200).

66641983660 is an abundant number, since it is smaller than the sum of its proper divisors (94433190740).

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

66641983660 is a wasteful number, since it uses less digits than its factorization.

66641983660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5135 (or 5133 counting only the distinct ones).

The product of its (nonzero) digits is 6718464, while the sum is 55.

The spelling of 66641983660 in words is "sixty-six billion, six hundred forty-one million, nine hundred eighty-three thousand, six hundred sixty".