12687129 has 36 divisors (see below), whose sum is σ = 22968036. Its totient is φ = 6689088.

The previous prime is 12687119. The next prime is 12687149. The reversal of 12687129 is 92178621.

It can be written as a sum of positive squares in 2 ways, for example, as 8277129 + 4410000 = 2877^2 + 2100^2 .

It is not a de Polignac number, because 12687129 - 2⁴ = 12687113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12687093 and 12687102.

It is not an unprimeable number, because it can be changed into a prime (12687109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4627 + ... + 6839.

It is an arithmetic number, because the mean of its divisors is an integer number (638001).

Almost surely, 2^12687129 is an apocalyptic number.

It is an amenable number.

12687129 is a deficient number, since it is larger than the sum of its proper divisors (10280907).

12687129 is a wasteful number, since it uses less digits than its factorization.

12687129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2246 (or 2236 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 12687129 is about 3561.8996336225. The cubic root of 12687129 is about 233.2318113904.

The spelling of 12687129 in words is "twelve million, six hundred eighty-seven thousand, one hundred twenty-nine".