136805 has 4 divisors (see below), whose sum is σ = 164172. Its totient is φ = 109440.

The previous prime is 136777. The next prime is 136811. The reversal of 136805 is 508631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 508631 = 29 ⋅17539.

It can be written as a sum of positive squares in 2 ways, for example, as 66049 + 70756 = 257^2 + 266^2 .

It is not a de Polignac number, because 136805 - 2¹⁰ = 135781 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 13676 + ... + 13685.

It is an arithmetic number, because the mean of its divisors is an integer number (41043).

2¹³⁶⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

136805 is a deficient number, since it is larger than the sum of its proper divisors (27367).

136805 is an equidigital number, since it uses as much as digits as its factorization.

136805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27366.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 136805 is about 369.8715993423. The cubic root of 136805 is about 51.5268970631.

The spelling of 136805 in words is "one hundred thirty-six thousand, eight hundred five".