1668686 has 12 divisors (see below), whose sum is σ = 2659848. Its totient is φ = 784992.

The previous prime is 1668683. The next prime is 1668721. The reversal of 1668686 is 6868661.

It is a nialpdrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668683) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 866 + ... + 2021.

It is an arithmetic number, because the mean of its divisors is an integer number (221654).

2^1668686 is an apocalyptic number.

1668686 is a deficient number, since it is larger than the sum of its proper divisors (991162).

1668686 is a wasteful number, since it uses less digits than its factorization.

1668686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2923 (or 2906 counting only the distinct ones).

The product of its digits is 82944, while the sum is 41.

The square root of 1668686 is about 1291.7762964229. The cubic root of 1668686 is about 118.6109745121.

The spelling of 1668686 in words is "one million, six hundred sixty-eight thousand, six hundred eighty-six".