133609 has 4 divisors (see below), whose sum is σ = 152704. Its totient is φ = 114516.

The previous prime is 133597. The next prime is 133631. The reversal of 133609 is 906331.

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 133609 - 2⁷ = 133481 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 133609.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133649) 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, 9537 + ... + 9550.

It is an arithmetic number, because the mean of its divisors is an integer number (38176).

2¹³³⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

133609 is a deficient number, since it is larger than the sum of its proper divisors (19095).

133609 is an equidigital number, since it uses as much as digits as its factorization.

133609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19094.

The product of its (nonzero) digits is 486, while the sum is 22.

The square root of 133609 is about 365.5256488948. The cubic root of 133609 is about 51.1224789179.

The spelling of 133609 in words is "one hundred thirty-three thousand, six hundred nine".