688434 has 16 divisors (see below), whose sum is σ = 1386720. Its totient is φ = 227840.

The previous prime is 688433. The next prime is 688447. The reversal of 688434 is 434886.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 688395 and 688404.

It is not an unprimeable number, because it can be changed into a prime (688433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 754 + ... + 1394.

It is an arithmetic number, because the mean of its divisors is an integer number (86670).

2⁶⁸⁸⁴³⁴ is an apocalyptic number.

688434 is an abundant number, since it is smaller than the sum of its proper divisors (698286).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

688434 is a wasteful number, since it uses less digits than its factorization.

688434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825.

The product of its digits is 18432, while the sum is 33.

The square root of 688434 is about 829.7192296193. The cubic root of 688434 is about 88.2986581198.

The spelling of 688434 in words is "six hundred eighty-eight thousand, four hundred thirty-four".