12129 has 8 divisors (see below), whose sum is σ = 17472. Its totient is φ = 7440.

The previous prime is 12119. The next prime is 12143. The reversal of 12129 is 92121.

It is a happy number.

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

It is not a de Polignac number, because 12129 - 2⁴ = 12113 is a prime.

It is a super-2 number, since 2×12129² = 294225282, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (12109) 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, 117 + ... + 194.

It is an arithmetic number, because the mean of its divisors is an integer number (2184).

2¹²¹²⁹ is an apocalyptic number.

It is an amenable number.

12129 is a deficient number, since it is larger than the sum of its proper divisors (5343).

12129 is a wasteful number, since it uses less digits than its factorization.

12129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327.

The product of its digits is 36, while the sum is 15.

The square root of 12129 is about 110.1317392944. The cubic root of 12129 is about 22.9760304793.

It can be divided in two parts, 1212 and 9, that added together give a palindrome (1221).

The spelling of 12129 in words is "twelve thousand, one hundred twenty-nine".