1688693 has 4 divisors (see below), whose sum is σ = 1691328. Its totient is φ = 1686060.

The previous prime is 1688681. The next prime is 1688741. The reversal of 1688693 is 3968861.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3968861 = 13 ⋅305297.

It is a cyclic number.

It is not a de Polignac number, because 1688693 - 2⁴ = 1688677 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1688693.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1688623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 338 + ... + 1868.

It is an arithmetic number, because the mean of its divisors is an integer number (422832).

2^1688693 is an apocalyptic number.

It is an amenable number.

1688693 is a deficient number, since it is larger than the sum of its proper divisors (2635).

1688693 is a wasteful number, since it uses less digits than its factorization.

1688693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2634.

The product of its digits is 62208, while the sum is 41.

The square root of 1688693 is about 1299.4972104626. The cubic root of 1688693 is about 119.0831281325.

The spelling of 1688693 in words is "one million, six hundred eighty-eight thousand, six hundred ninety-three".