687424 has 28 divisors (see below), whose sum is σ = 1426464. Its totient is φ = 328064.

The previous prime is 687413. The next prime is 687431. The reversal of 687424 is 424786.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1239 + ... + 1705.

2⁶⁸⁷⁴²⁴ is an apocalyptic number.

687424 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 687424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (713232).

687424 is an abundant number, since it is smaller than the sum of its proper divisors (739040).

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

687424 is a wasteful number, since it uses less digits than its factorization.

687424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502 (or 492 counting only the distinct ones).

The product of its digits is 10752, while the sum is 31.

The square root of 687424 is about 829.1103665978. The cubic root of 687424 is about 88.2554560636.

It can be divided in two parts, 687 and 424, that added together give a palindrome (1111).

The spelling of 687424 in words is "six hundred eighty-seven thousand, four hundred twenty-four".