688636 has 48 divisors (see below), whose sum is σ = 1481760. Its totient is φ = 276480.

The previous prime is 688631. The next prime is 688637. The reversal of 688636 is 636886.

688636 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 688595 and 688604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688631) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16776 + ... + 16816.

It is an arithmetic number, because the mean of its divisors is an integer number (30870).

2⁶⁸⁸⁶³⁶ is an apocalyptic number.

It is an amenable number.

688636 is an abundant number, since it is smaller than the sum of its proper divisors (793124).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

688636 is a wasteful number, since it uses less digits than its factorization.

688636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94 (or 92 counting only the distinct ones).

The product of its digits is 41472, while the sum is 37.

The square root of 688636 is about 829.8409486161. The cubic root of 688636 is about 88.3072934597.

The spelling of 688636 in words is "six hundred eighty-eight thousand, six hundred thirty-six".