686255 has 4 divisors (see below), whose sum is σ = 823512. Its totient is φ = 549000.

The previous prime is 686209. The next prime is 686267. The reversal of 686255 is 552686.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 552686 = 2 ⋅276343.

It is not a de Polignac number, because 686255 - 2¹⁰ = 685231 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 686255.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68621 + ... + 68630.

It is an arithmetic number, because the mean of its divisors is an integer number (205878).

2⁶⁸⁶²⁵⁵ is an apocalyptic number.

686255 is a deficient number, since it is larger than the sum of its proper divisors (137257).

686255 is a wasteful number, since it uses less digits than its factorization.

686255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137256.

The product of its digits is 14400, while the sum is 32.

The square root of 686255 is about 828.4050941417. The cubic root of 686255 is about 88.2054000255.

The spelling of 686255 in words is "six hundred eighty-six thousand, two hundred fifty-five".