135823 has 4 divisors (see below), whose sum is σ = 137808. Its totient is φ = 133840.

The previous prime is 135799. The next prime is 135829. The reversal of 135823 is 328531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 328531 = 7 ⋅46933.

It is a cyclic number.

It is not a de Polignac number, because 135823 - 2¹⁷ = 4751 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 135794 and 135803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135829) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 886 + ... + 1027.

It is an arithmetic number, because the mean of its divisors is an integer number (34452).

2¹³⁵⁸²³ is an apocalyptic number.

135823 is a deficient number, since it is larger than the sum of its proper divisors (1985).

135823 is an equidigital number, since it uses as much as digits as its factorization.

135823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1984.

The product of its digits is 720, while the sum is 22.

The square root of 135823 is about 368.5417208404. The cubic root of 135823 is about 51.4033124786.

The spelling of 135823 in words is "one hundred thirty-five thousand, eight hundred twenty-three".