133165 has 4 divisors (see below), whose sum is σ = 159804. Its totient is φ = 106528.

The previous prime is 133157. The next prime is 133169. The reversal of 133165 is 561331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 561331 = 41 ⋅13691.

It can be written as a sum of positive squares in 2 ways, for example, as 101124 + 32041 = 318^2 + 179^2 .

It is a cyclic number.

It is not a de Polignac number, because 133165 - 2³ = 133157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133169) 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, 13312 + ... + 13321.

It is an arithmetic number, because the mean of its divisors is an integer number (39951).

2¹³³¹⁶⁵ is an apocalyptic number.

It is an amenable number.

133165 is a deficient number, since it is larger than the sum of its proper divisors (26639).

133165 is an equidigital number, since it uses as much as digits as its factorization.

133165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26638.

The product of its digits is 270, while the sum is 19.

The square root of 133165 is about 364.9177989630. The cubic root of 133165 is about 51.0657872021.

Adding to 133165 its reverse (561331), we get a palindrome (694496).

It can be divided in two parts, 133 and 165, that multiplied together give a triangular number (21945 = T₂₀₉).

The spelling of 133165 in words is "one hundred thirty-three thousand, one hundred sixty-five".