687345 has 8 divisors (see below), whose sum is σ = 1099776. Its totient is φ = 366576.

The previous prime is 687343. The next prime is 687359. The reversal of 687345 is 543786.

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

It is not a de Polignac number, because 687345 - 2¹ = 687343 is a prime.

It is a Curzon number.

687345 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (687341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22897 + ... + 22926.

It is an arithmetic number, because the mean of its divisors is an integer number (137472).

2⁶⁸⁷³⁴⁵ is an apocalyptic number.

It is an amenable number.

687345 is a deficient number, since it is larger than the sum of its proper divisors (412431).

687345 is a wasteful number, since it uses less digits than its factorization.

687345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45831.

The product of its digits is 20160, while the sum is 33.

The square root of 687345 is about 829.0627238032. The cubic root of 687345 is about 88.2520751090.

Adding to 687345 its sum of digits (33), we get a triangular number (687378 = T₁₁₇₂).

The spelling of 687345 in words is "six hundred eighty-seven thousand, three hundred forty-five".