135986 has 4 divisors (see below), whose sum is σ = 203982. Its totient is φ = 67992.

The previous prime is 135979. The next prime is 136013. The reversal of 135986 is 689531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 689531 = 257 ⋅2683.

It can be written as a sum of positive squares in only one way, i.e., 101761 + 34225 = 319^2 + 185^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33995 + ... + 33998.

2¹³⁵⁹⁸⁶ is an apocalyptic number.

135986 is a deficient number, since it is larger than the sum of its proper divisors (67996).

135986 is an equidigital number, since it uses as much as digits as its factorization.

135986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67995.

The product of its digits is 6480, while the sum is 32.

The square root of 135986 is about 368.7627963881. The cubic root of 135986 is about 51.4238671476.

The spelling of 135986 in words is "one hundred thirty-five thousand, nine hundred eighty-six".