687385 has 4 divisors (see below), whose sum is σ = 824868. Its totient is φ = 549904.

The previous prime is 687383. The next prime is 687389. The reversal of 687385 is 583786.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 257049 + 430336 = 507^2 + 656^2 .

It is a cyclic number.

It is not a de Polignac number, because 687385 - 2¹ = 687383 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68734 + ... + 68743.

It is an arithmetic number, because the mean of its divisors is an integer number (206217).

2⁶⁸⁷³⁸⁵ is an apocalyptic number.

It is an amenable number.

687385 is a deficient number, since it is larger than the sum of its proper divisors (137483).

687385 is a wasteful number, since it uses less digits than its factorization.

687385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137482.

The product of its digits is 40320, while the sum is 37.

The square root of 687385 is about 829.0868470794. The cubic root of 687385 is about 88.2537870171.

The spelling of 687385 in words is "six hundred eighty-seven thousand, three hundred eighty-five".