684912 has 40 divisors (see below), whose sum is σ = 1864960. Its totient is φ = 216000.

The previous prime is 684889. The next prime is 684923. The reversal of 684912 is 219486.

684912 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 684912.

It is a congruent number.

It is an unprimeable number.

684912 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, 537 + ... + 1287.

It is an arithmetic number, because the mean of its divisors is an integer number (46624).

2⁶⁸⁴⁹¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 684912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (932480).

684912 is an abundant number, since it is smaller than the sum of its proper divisors (1180048).

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

684912 is a wasteful number, since it uses less digits than its factorization.

684912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781 (or 775 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The square root of 684912 is about 827.5941034106. The cubic root of 684912 is about 88.1478231716.

It can be divided in two parts, 684 and 912, that added together give a triangular number (1596 = T₅₆).

The spelling of 684912 in words is "six hundred eighty-four thousand, nine hundred twelve".