135686 has 4 divisors (see below), whose sum is σ = 203532. Its totient is φ = 67842.

The previous prime is 135671. The next prime is 135697. The reversal of 135686 is 686531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 686531 = 739 ⋅929.

It is a nialpdrome in base 12.

It is a congruent number.

It is an unprimeable number.

135686 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33920 + ... + 33923.

It is an arithmetic number, because the mean of its divisors is an integer number (50883).

2¹³⁵⁶⁸⁶ is an apocalyptic number.

135686 is a deficient number, since it is larger than the sum of its proper divisors (67846).

135686 is an equidigital number, since it uses as much as digits as its factorization.

135686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67845.

The product of its digits is 4320, while the sum is 29.

The square root of 135686 is about 368.3558062526. The cubic root of 135686 is about 51.3860237452.

The spelling of 135686 in words is "one hundred thirty-five thousand, six hundred eighty-six".