12129217 has 2 divisors, whose sum is σ = 12129218. Its totient is φ = 12129216.

The previous prime is 12129197. The next prime is 12129233. The reversal of 12129217 is 71292121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6195121 + 5934096 = 2489^2 + 2436^2 .

It is a cyclic number.

It is not a de Polignac number, because 12129217 - 2¹⁵ = 12096449 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12129191 and 12129200.

It is not a weakly prime, because it can be changed into another prime (12129287) 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 as a sum of consecutive naturals, namely, 6064608 + 6064609.

It is an arithmetic number, because the mean of its divisors is an integer number (6064609).

Almost surely, 2^12129217 is an apocalyptic number.

It is an amenable number.

12129217 is a deficient number, since it is larger than the sum of its proper divisors (1).

12129217 is an equidigital number, since it uses as much as digits as its factorization.

12129217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 504, while the sum is 25.

The square root of 12129217 is about 3482.7025425666. The cubic root of 12129217 is about 229.7616749991.

The spelling of 12129217 in words is "twelve million, one hundred twenty-nine thousand, two hundred seventeen".