684389 has 8 divisors (see below), whose sum is σ = 718200. Its totient is φ = 651456.

The previous prime is 684379. The next prime is 684407. The reversal of 684389 is 983486.

684389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 390625 + 293764 = 625^2 + 542^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 684389 - 2⁴ = 684373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1787 + ... + 2135.

It is an arithmetic number, because the mean of its divisors is an integer number (89775).

2⁶⁸⁴³⁸⁹ is an apocalyptic number.

It is an amenable number.

684389 is a deficient number, since it is larger than the sum of its proper divisors (33811).

684389 is a wasteful number, since it uses less digits than its factorization.

684389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 439.

The product of its digits is 41472, while the sum is 38.

The square root of 684389 is about 827.2780669158. The cubic root of 684389 is about 88.1253808477.

The spelling of 684389 in words is "six hundred eighty-four thousand, three hundred eighty-nine".