686426 has 16 divisors (see below), whose sum is σ = 1174824. Its totient is φ = 297984.

The previous prime is 686423. The next prime is 686437. The reversal of 686426 is 624686.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 421201 + 265225 = 649^2 + 515^2 .

It is a junction number, because it is equal to n+sod(n) for n = 686392 and 686401.

It is not an unprimeable number, because it can be changed into a prime (686423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 335 + ... + 1218.

2⁶⁸⁶⁴²⁶ is an apocalyptic number.

686426 is a deficient number, since it is larger than the sum of its proper divisors (488398).

686426 is a wasteful number, since it uses less digits than its factorization.

686426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1585.

The product of its digits is 13824, while the sum is 32.

The square root of 686426 is about 828.5082980876. The cubic root of 686426 is about 88.2127257139.

The spelling of 686426 in words is "six hundred eighty-six thousand, four hundred twenty-six".