135609 has 8 divisors (see below), whose sum is σ = 191520. Its totient is φ = 85056.

The previous prime is 135607. The next prime is 135613. The reversal of 135609 is 906531.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 135609 - 2¹ = 135607 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1279 + ... + 1380.

It is an arithmetic number, because the mean of its divisors is an integer number (23940).

2¹³⁵⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

135609 is a deficient number, since it is larger than the sum of its proper divisors (55911).

135609 is a wasteful number, since it uses less digits than its factorization.

135609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2679.

The product of its (nonzero) digits is 810, while the sum is 24.

The square root of 135609 is about 368.2512729102. The cubic root of 135609 is about 51.3763016110.

It can be divided in two parts, 135 and 609, that multiplied together give a triangular number (82215 = T₄₀₅).

The spelling of 135609 in words is "one hundred thirty-five thousand, six hundred nine".