133823 has 4 divisors (see below), whose sum is σ = 134808. Its totient is φ = 132840.

The previous prime is 133813. The next prime is 133831. The reversal of 133823 is 328331.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133823 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 133795 and 133804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133813) 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, 248 + ... + 573.

It is an arithmetic number, because the mean of its divisors is an integer number (33702).

2¹³³⁸²³ is an apocalyptic number.

133823 is a deficient number, since it is larger than the sum of its proper divisors (985).

133823 is an equidigital number, since it uses as much as digits as its factorization.

133823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 984.

The product of its digits is 432, while the sum is 20.

The square root of 133823 is about 365.8182608892. The cubic root of 133823 is about 51.1497584544.

The spelling of 133823 in words is "one hundred thirty-three thousand, eight hundred twenty-three".