1688668 has 12 divisors (see below), whose sum is σ = 2999752. Its totient is φ = 831600.

The previous prime is 1688657. The next prime is 1688669. The reversal of 1688668 is 8668861.

It is a happy number.

It is a super-2 number, since 2×1688668² = 5703199228448, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1688669) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2883 + ... + 3418.

2^1688668 is an apocalyptic number.

It is an amenable number.

1688668 is a deficient number, since it is larger than the sum of its proper divisors (1311084).

1688668 is a wasteful number, since it uses less digits than its factorization.

1688668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6372 (or 6370 counting only the distinct ones).

The product of its digits is 110592, while the sum is 43.

The square root of 1688668 is about 1299.4875913221. The cubic root of 1688668 is about 119.0825404802.

It can be divided in two parts, 168 and 8668, that added together give a square (8836 = 94²).

The spelling of 1688668 in words is "one million, six hundred eighty-eight thousand, six hundred sixty-eight".