686071 has 4 divisors (see below), whose sum is σ = 722200. Its totient is φ = 649944.

The previous prime is 686057. The next prime is 686087. The reversal of 686071 is 170686.

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 686071 - 2⁵ = 686039 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686011) 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, 18036 + ... + 18073.

It is an arithmetic number, because the mean of its divisors is an integer number (180550).

2⁶⁸⁶⁰⁷¹ is an apocalyptic number.

686071 is a deficient number, since it is larger than the sum of its proper divisors (36129).

686071 is a wasteful number, since it uses less digits than its factorization.

686071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36128.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 686071 is about 828.2940299193. The cubic root of 686071 is about 88.1975160542.

The spelling of 686071 in words is "six hundred eighty-six thousand, seventy-one".