133989 has 8 divisors (see below), whose sum is σ = 181920. Its totient is φ = 87696.

The previous prime is 133981. The next prime is 133993. The reversal of 133989 is 989331.

133989 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 133989 - 2³ = 133981 is a prime.

133989 is strictly pandigital in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133981) 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, 202 + ... + 555.

It is an arithmetic number, because the mean of its divisors is an integer number (22740).

2¹³³⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

133989 is a deficient number, since it is larger than the sum of its proper divisors (47931).

133989 is an equidigital number, since it uses as much as digits as its factorization.

133989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 819.

The product of its digits is 5832, while the sum is 33.

The square root of 133989 is about 366.0450791911. The cubic root of 133989 is about 51.1708991938.

Subtracting from 133989 its sum of digits (33), we obtain a square (133956 = 366²).

The spelling of 133989 in words is "one hundred thirty-three thousand, nine hundred eighty-nine".