687648 has 96 divisors (see below), whose sum is σ = 2116800. Its totient is φ = 193536.

The previous prime is 687647. The next prime is 687679. The reversal of 687648 is 846786.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (687641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23698 + ... + 23726.

It is an arithmetic number, because the mean of its divisors is an integer number (22050).

2⁶⁸⁷⁶⁴⁸ 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 687648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1058400).

687648 is an abundant number, since it is smaller than the sum of its proper divisors (1429152).

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

687648 is a wasteful number, since it uses less digits than its factorization.

687648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74 (or 66 counting only the distinct ones).

The product of its digits is 64512, while the sum is 39.

The square root of 687648 is about 829.2454401442. The cubic root of 687648 is about 88.2650411597.

The spelling of 687648 in words is "six hundred eighty-seven thousand, six hundred forty-eight".