66991135104 has 256 divisors, whose sum is σ = 217176768000. Its totient is φ = 20234852352.

The previous prime is 66991135097. The next prime is 66991135109. The reversal of 66991135104 is 40153119966.

It is a self number, because there is not a number n which added to its sum of digits gives 66991135104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66991135109) 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, 1488094 + ... + 1532450.

It is an arithmetic number, because the mean of its divisors is an integer number (848346750).

Almost surely, 2^66991135104 is an apocalyptic number.

66991135104 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 66991135104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108588384000).

66991135104 is an abundant number, since it is smaller than the sum of its proper divisors (150185632896).

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

66991135104 is a wasteful number, since it uses less digits than its factorization.

66991135104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44422 (or 44404 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 45.

The spelling of 66991135104 in words is "sixty-six billion, nine hundred ninety-one million, one hundred thirty-five thousand, one hundred four".