66996835931784 has 128 divisors (see below), whose sum is σ = 188885765468160. Its totient is φ = 19618731360000.

The previous prime is 66996835931749. The next prime is 66996835931869. The reversal of 66996835931784 is 48713953869966.

It is a junction number, because it is equal to n+sod(n) for n = 66996835931697 and 66996835931706.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 268387 + ... + 11578674.

It is an arithmetic number, because the mean of its divisors is an integer number (1475670042720).

Almost surely, 2^{66996835931784} 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 66996835931784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94442882734080).

66996835931784 is an abundant number, since it is smaller than the sum of its proper divisors (121888929536376).

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

66996835931784 is a wasteful number, since it uses less digits than its factorization.

66996835931784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11847803 (or 11847799 counting only the distinct ones).

The product of its digits is 12697896960, while the sum is 84.

The spelling of 66996835931784 in words is "sixty-six trillion, nine hundred ninety-six billion, eight hundred thirty-five million, nine hundred thirty-one thousand, seven hundred eighty-four".