686455 has 16 divisors (see below), whose sum is σ = 1027584. Its totient is φ = 427680.

The previous prime is 686453. The next prime is 686473. The reversal of 686455 is 554686.

It is not a de Polignac number, because 686455 - 2¹ = 686453 is a prime.

It is a Duffinian number.

686455 is a lucky number.

It is a plaindrome in base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 686455.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 507 + ... + 1276.

It is an arithmetic number, because the mean of its divisors is an integer number (64224).

2⁶⁸⁶⁴⁵⁵ is an apocalyptic number.

686455 is a deficient number, since it is larger than the sum of its proper divisors (341129).

686455 is a wasteful number, since it uses less digits than its factorization.

686455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1806.

The product of its digits is 28800, while the sum is 34.

The square root of 686455 is about 828.5257992362. The cubic root of 686455 is about 88.2139679614.

Subtracting from 686455 its reverse (554686), we obtain a square (131769 = 363²).

The spelling of 686455 in words is "six hundred eighty-six thousand, four hundred fifty-five".