668937739866 has 32 divisors (see below), whose sum is σ = 1459550181888. Its totient is φ = 202701509040.

The previous prime is 668937739849. The next prime is 668937739867.

668937739866 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 668937739791 and 668937739800.

It is not an unprimeable number, because it can be changed into a prime (668937739867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1985035 + ... + 2297441.

It is an arithmetic number, because the mean of its divisors is an integer number (45610943184).

Almost surely, 2^668937739866 is an apocalyptic number.

668937739866 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

668937739866 is an abundant number, since it is smaller than the sum of its proper divisors (790612442022).

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

668937739866 is a wasteful number, since it uses less digits than its factorization.

668937739866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344866.

The product of its digits is 2962842624, while the sum is 78.

The spelling of 668937739866 in words is "six hundred sixty-eight billion, nine hundred thirty-seven million, seven hundred thirty-nine thousand, eight hundred sixty-six".