687319 has 4 divisors (see below), whose sum is σ = 694096. Its totient is φ = 680544.

The previous prime is 687317. The next prime is 687331. The reversal of 687319 is 913786.

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

It is a cyclic number.

It is not a de Polignac number, because 687319 - 2¹ = 687317 is a prime.

It is a super-2 number, since 2×687319² = 944814815522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687311) 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 3 ways as a sum of consecutive naturals, for example, 3234 + ... + 3439.

It is an arithmetic number, because the mean of its divisors is an integer number (173524).

2⁶⁸⁷³¹⁹ is an apocalyptic number.

687319 is a deficient number, since it is larger than the sum of its proper divisors (6777).

687319 is a wasteful number, since it uses less digits than its factorization.

687319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6776.

The product of its digits is 9072, while the sum is 34.

The square root of 687319 is about 829.0470432973. The cubic root of 687319 is about 88.2509623331.

The spelling of 687319 in words is "six hundred eighty-seven thousand, three hundred nineteen".