133309 has 4 divisors (see below), whose sum is σ = 145440. Its totient is φ = 121180.

The previous prime is 133303. The next prime is 133319. The reversal of 133309 is 903331.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 133309 - 2⁵ = 133277 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 (133303) 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, 6049 + ... + 6070.

It is an arithmetic number, because the mean of its divisors is an integer number (36360).

2¹³³³⁰⁹ is an apocalyptic number.

It is an amenable number.

133309 is a deficient number, since it is larger than the sum of its proper divisors (12131).

133309 is a wasteful number, since it uses less digits than its factorization.

133309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12130.

The product of its (nonzero) digits is 243, while the sum is 19.

The square root of 133309 is about 365.1150503608. The cubic root of 133309 is about 51.0841874934.

The spelling of 133309 in words is "one hundred thirty-three thousand, three hundred nine".