687740 has 24 divisors (see below), whose sum is σ = 1460592. Its totient is φ = 272000.

The previous prime is 687737. The next prime is 687749. The reversal of 687740 is 47786.

It is a junction number, because it is equal to n+sod(n) for n = 687697 and 687706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2615 + ... + 2865.

It is an arithmetic number, because the mean of its divisors is an integer number (60858).

2⁶⁸⁷⁷⁴⁰ is an apocalyptic number.

It is an amenable number.

687740 is an abundant number, since it is smaller than the sum of its proper divisors (772852).

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

687740 is a wasteful number, since it uses less digits than its factorization.

687740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397 (or 395 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 687740 is about 829.3009104059. The cubic root of 687740 is about 88.2689772926.

The spelling of 687740 in words is "six hundred eighty-seven thousand, seven hundred forty".