686224 has 40 divisors (see below), whose sum is σ = 1660608. Its totient is φ = 266880.

The previous prime is 686209. The next prime is 686267. The reversal of 686224 is 422686.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a nialpdrome in base 7.

It is a junction number, because it is equal to n+sod(n) for n = 686192 and 686201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 954 + ... + 1510.

2⁶⁸⁶²²⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (830304).

686224 is an abundant number, since it is smaller than the sum of its proper divisors (974384).

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

686224 is a wasteful number, since it uses less digits than its factorization.

686224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 583 (or 577 counting only the distinct ones).

The product of its digits is 4608, while the sum is 28.

The square root of 686224 is about 828.3863832778. The cubic root of 686224 is about 88.2040718465.

It can be divided in two parts, 6862 and 24, that added together give a palindrome (6886).

The spelling of 686224 in words is "six hundred eighty-six thousand, two hundred twenty-four".