687361 has 4 divisors (see below), whose sum is σ = 727812. Its totient is φ = 646912.

The previous prime is 687359. The next prime is 687383. The reversal of 687361 is 163786.

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 309136 + 378225 = 556^2 + 615^2 .

It is a cyclic number.

It is not a de Polignac number, because 687361 - 2¹ = 687359 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20200 + ... + 20233.

It is an arithmetic number, because the mean of its divisors is an integer number (181953).

2⁶⁸⁷³⁶¹ is an apocalyptic number.

It is an amenable number.

687361 is a deficient number, since it is larger than the sum of its proper divisors (40451).

687361 is a wasteful number, since it uses less digits than its factorization.

687361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40450.

The product of its digits is 6048, while the sum is 31.

The square root of 687361 is about 829.0723731979. The cubic root of 687361 is about 88.2527598802.

The spelling of 687361 in words is "six hundred eighty-seven thousand, three hundred sixty-one".