686791 has 8 divisors (see below), whose sum is σ = 804384. Its totient is φ = 574080.

The previous prime is 686789. The next prime is 686797. The reversal of 686791 is 197686.

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

It is a cyclic number.

It is not a de Polignac number, because 686791 - 2¹ = 686789 is a prime.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 686791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686797) 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, 910 + ... + 1483.

It is an arithmetic number, because the mean of its divisors is an integer number (100548).

2⁶⁸⁶⁷⁹¹ is an apocalyptic number.

686791 is a deficient number, since it is larger than the sum of its proper divisors (117593).

686791 is a wasteful number, since it uses less digits than its factorization.

686791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2441.

The product of its digits is 18144, while the sum is 37.

The square root of 686791 is about 828.7285442170. The cubic root of 686791 is about 88.2283583481.

It can be divided in two parts, 68 and 6791, that added together give a cube (6859 = 19³).

The spelling of 686791 in words is "six hundred eighty-six thousand, seven hundred ninety-one".