684826 has 4 divisors (see below), whose sum is σ = 1027242. Its totient is φ = 342412.

The previous prime is 684809. The next prime is 684829. The reversal of 684826 is 628486.

684826 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, and also an emirpimes, since its reverse is a distinct semiprime: 628486 = 2 ⋅314243.

It can be written as a sum of positive squares in only one way, i.e., 525625 + 159201 = 725^2 + 399^2 .

It is a junction number, because it is equal to n+sod(n) for n = 684791 and 684800.

It is not an unprimeable number, because it can be changed into a prime (684829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171205 + ... + 171208.

2⁶⁸⁴⁸²⁶ is an apocalyptic number.

684826 is a deficient number, since it is larger than the sum of its proper divisors (342416).

684826 is a wasteful number, since it uses less digits than its factorization.

684826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342415.

The product of its digits is 18432, while the sum is 34.

The square root of 684826 is about 827.5421439419. The cubic root of 684826 is about 88.1441336319.

The spelling of 684826 in words is "six hundred eighty-four thousand, eight hundred twenty-six".