684636 has 24 divisors (see below), whose sum is σ = 1626240. Its totient is φ = 224112.

The previous prime is 684617. The next prime is 684637. The reversal of 684636 is 636486.

684636 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 = 684597 and 684606.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 684636.

It is not an unprimeable number, because it can be changed into a prime (684637) by changing a digit.

684636 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 225 + ... + 1191.

It is an arithmetic number, because the mean of its divisors is an integer number (67760).

2⁶⁸⁴⁶³⁶ is an apocalyptic number.

It is an amenable number.

684636 is an abundant number, since it is smaller than the sum of its proper divisors (941604).

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

684636 is a wasteful number, since it uses less digits than its factorization.

684636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1033 (or 1031 counting only the distinct ones).

The product of its digits is 20736, while the sum is 33.

The square root of 684636 is about 827.4273381996. The cubic root of 684636 is about 88.1359812280.

The spelling of 684636 in words is "six hundred eighty-four thousand, six hundred thirty-six".