684375 has 24 divisors (see below), whose sum is σ = 1156176. Its totient is φ = 360000.

The previous prime is 684373. The next prime is 684379. The reversal of 684375 is 573486.

It is not a de Polignac number, because 684375 - 2¹ = 684373 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684373) 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 23 ways as a sum of consecutive naturals, for example, 9339 + ... + 9411.

It is an arithmetic number, because the mean of its divisors is an integer number (48174).

2⁶⁸⁴³⁷⁵ is an apocalyptic number.

684375 is a deficient number, since it is larger than the sum of its proper divisors (471801).

684375 is an frugal number, since it uses more digits than its factorization.

684375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101 (or 81 counting only the distinct ones).

The product of its digits is 20160, while the sum is 33.

The square root of 684375 is about 827.2696053887. The cubic root of 684375 is about 88.1247799401.

Subtracting from 684375 its reverse (573486), we obtain a square (110889 = 333²).

The spelling of 684375 in words is "six hundred eighty-four thousand, three hundred seventy-five".