66998063808 has 336 divisors, whose sum is σ = 218798973120. Its totient is φ = 19448377344.

The previous prime is 66998063791. The next prime is 66998063813. The reversal of 66998063808 is 80836089966.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 917781660 + ... + 917781732.

It is an arithmetic number, because the mean of its divisors is an integer number (651187420).

Almost surely, 2^66998063808 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 66998063808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109399486560).

66998063808 is an abundant number, since it is smaller than the sum of its proper divisors (151800909312).

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

66998063808 is an equidigital number, since it uses as much as digits as its factorization.

66998063808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273 (or 114 counting only the distinct ones).

The product of its (nonzero) digits is 26873856, while the sum is 63.

The spelling of 66998063808 in words is "sixty-six billion, nine hundred ninety-eight million, sixty-three thousand, eight hundred eight".