1681688 has 16 divisors (see below), whose sum is σ = 3255360. Its totient is φ = 813600.

The previous prime is 1681679. The next prime is 1681703. The reversal of 1681688 is 8861861.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3143 + ... + 3638.

It is an arithmetic number, because the mean of its divisors is an integer number (203460).

2^1681688 is an apocalyptic number.

It is an amenable number.

1681688 is a deficient number, since it is larger than the sum of its proper divisors (1573672).

1681688 is a wasteful number, since it uses less digits than its factorization.

1681688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6818 (or 6814 counting only the distinct ones).

The product of its digits is 18432, while the sum is 38.

The square root of 1681688 is about 1296.7991363353. The cubic root of 1681688 is about 118.9182405702.

The spelling of 1681688 in words is "one million, six hundred eighty-one thousand, six hundred eighty-eight".