668391682 has 16 divisors (see below), whose sum is σ = 1182776832. Its totient is φ = 277212960.

The previous prime is 668391679. The next prime is 668391683. The reversal of 668391682 is 286193866.

It is a happy number.

668391682 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (668391683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 769603 + ... + 770470.

It is an arithmetic number, because the mean of its divisors is an integer number (73923552).

Almost surely, 2^668391682 is an apocalyptic number.

668391682 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

668391682 is a deficient number, since it is larger than the sum of its proper divisors (514385150).

668391682 is a wasteful number, since it uses less digits than its factorization.

668391682 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1540113.

The product of its digits is 746496, while the sum is 49.

The square root of 668391682 is about 25853.2721720095. The cubic root of 668391682 is about 874.3332856437. Note that the first 3 decimals are identical.

The spelling of 668391682 in words is "six hundred sixty-eight million, three hundred ninety-one thousand, six hundred eighty-two".