133509 has 8 divisors (see below), whose sum is σ = 179712. Its totient is φ = 88160.

The previous prime is 133499. The next prime is 133519. The reversal of 133509 is 905331.

It is an interprime number because it is at equal distance from previous prime (133499) and next prime (133519).

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

It is a cyclic number.

It is not a de Polignac number, because 133509 - 2⁴ = 133493 is a prime.

133509 is a lucky number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133519) 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, 457 + ... + 689.

It is an arithmetic number, because the mean of its divisors is an integer number (22464).

2¹³³⁵⁰⁹ is an apocalyptic number.

It is an amenable number.

133509 is a deficient number, since it is larger than the sum of its proper divisors (46203).

133509 is a wasteful number, since it uses less digits than its factorization.

133509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427.

The product of its (nonzero) digits is 405, while the sum is 21.

The square root of 133509 is about 365.3888339837. The cubic root of 133509 is about 51.1097214843.

The spelling of 133509 in words is "one hundred thirty-three thousand, five hundred nine".