686887 has 4 divisors (see below), whose sum is σ = 690640. Its totient is φ = 683136.

The previous prime is 686879. The next prime is 686891. The reversal of 686887 is 788686.

It is a happy number.

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 686887 - 2³ = 686879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686837) 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, 1587 + ... + 1972.

It is an arithmetic number, because the mean of its divisors is an integer number (172660).

2⁶⁸⁶⁸⁸⁷ is an apocalyptic number.

686887 is the 479-th hex number.

686887 is a deficient number, since it is larger than the sum of its proper divisors (3753).

686887 is a wasteful number, since it uses less digits than its factorization.

686887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3752.

The product of its digits is 129024, while the sum is 43.

The square root of 686887 is about 828.7864622446. The cubic root of 686887 is about 88.2324690250.

The spelling of 686887 in words is "six hundred eighty-six thousand, eight hundred eighty-seven".