12789 has 18 divisors (see below), whose sum is σ = 22230. Its totient is φ = 7056.

The previous prime is 12781. The next prime is 12791. The reversal of 12789 is 98721.

12789 = T₁₄ + T₁₅ + ... + T₄₂.

It can be written as a sum of positive squares in only one way, i.e., 11025 + 1764 = 105^2 + 42^2 .

It is not a de Polignac number, because 12789 - 2³ = 12781 is a prime.

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

It is a Curzon number.

It is a plaindrome in base 10.

It is a nialpdrome in base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12781) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 427 + ... + 455.

It is an arithmetic number, because the mean of its divisors is an integer number (1235).

2¹²⁷⁸⁹ is an apocalyptic number.

It is an amenable number.

12789 is a deficient number, since it is larger than the sum of its proper divisors (9441).

12789 is a wasteful number, since it uses less digits than its factorization.

12789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49 (or 39 counting only the distinct ones).

The product of its digits is 1008, while the sum is 27.

The square root of 12789 is about 113.0884609498. The cubic root of 12789 is about 23.3854391113.

Subtracting from 12789 its product of digits (1008), we obtain a triangular number (11781 = T₁₅₃).

It can be divided in two parts, 127 and 89, that added together give a cube (216 = 6³).

The spelling of 12789 in words is "twelve thousand, seven hundred eighty-nine".