684428 has 12 divisors (see below), whose sum is σ = 1203552. Its totient is φ = 340560.

The previous prime is 684427. The next prime is 684433. The reversal of 684428 is 824486.

It is a junction number, because it is equal to n+sod(n) for n = 684394 and 684403.

It is not an unprimeable number, because it can be changed into a prime (684427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1373 + ... + 1803.

It is an arithmetic number, because the mean of its divisors is an integer number (100296).

2⁶⁸⁴⁴²⁸ is an apocalyptic number.

It is an amenable number.

684428 is a deficient number, since it is larger than the sum of its proper divisors (519124).

684428 is a wasteful number, since it uses less digits than its factorization.

684428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 832 (or 830 counting only the distinct ones).

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

The square root of 684428 is about 827.3016378565. The cubic root of 684428 is about 88.1270547615.

The spelling of 684428 in words is "six hundred eighty-four thousand, four hundred twenty-eight".