684842 has 4 divisors (see below), whose sum is σ = 1027266. Its totient is φ = 342420.

The previous prime is 684841. The next prime is 684857. The reversal of 684842 is 248486.

684842 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 358801 + 326041 = 599^2 + 571^2 .

It is a junction number, because it is equal to n+sod(n) for n = 684799 and 684808.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 684842.

It is not an unprimeable number, because it can be changed into a prime (684841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171209 + ... + 171212.

2⁶⁸⁴⁸⁴² is an apocalyptic number.

684842 is a deficient number, since it is larger than the sum of its proper divisors (342424).

684842 is a wasteful number, since it uses less digits than its factorization.

684842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342423.

The product of its digits is 12288, while the sum is 32.

The square root of 684842 is about 827.5518110668. The cubic root of 684842 is about 88.1448200813.

It can be divided in two parts, 68484 and 2, that added together give a palindrome (68486).

The spelling of 684842 in words is "six hundred eighty-four thousand, eight hundred forty-two".