687439 has 8 divisors (see below), whose sum is σ = 733040. Its totient is φ = 642816.

The previous prime is 687437. The next prime is 687443. The reversal of 687439 is 934786.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 687439 - 2¹ = 687437 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 687398 and 687407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687431) 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, 1657 + ... + 2029.

It is an arithmetic number, because the mean of its divisors is an integer number (91630).

2⁶⁸⁷⁴³⁹ is an apocalyptic number.

687439 is a deficient number, since it is larger than the sum of its proper divisors (45601).

687439 is a wasteful number, since it uses less digits than its factorization.

687439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 489.

The product of its digits is 36288, while the sum is 37.

The square root of 687439 is about 829.1194123888. The cubic root of 687439 is about 88.2560979878.

The spelling of 687439 in words is "six hundred eighty-seven thousand, four hundred thirty-nine".