668835538866 has 96 divisors (see below), whose sum is σ = 1608962097600. Its totient is φ = 199083171840.

The previous prime is 668835538859. The next prime is 668835538871.

668835538866 is a `hidden beast` number, since 6 + 6 + 8 + 8 + 3 + 5 + 538 + 86 + 6 = 666.

668835538866 is nontrivially palindromic in base 10.

It is a super-3 number, since 3×668835538866³ (a number of 36 digits) contains 333 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 668835538794 and 668835538803.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 15035890 + ... + 15080306.

It is an arithmetic number, because the mean of its divisors is an integer number (16760021850).

Almost surely, 2^668835538866 is an apocalyptic number.

668835538866 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 668835538866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (804481048800).

668835538866 is an abundant number, since it is smaller than the sum of its proper divisors (940126558734).

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

668835538866 is a wasteful number, since it uses less digits than its factorization.

668835538866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45784 (or 45781 counting only the distinct ones).

The product of its digits is 1194393600, while the sum is 72.

The spelling of 668835538866 in words is "six hundred sixty-eight billion, eight hundred thirty-five million, five hundred thirty-eight thousand, eight hundred sixty-six".