12172309 has 2 divisors, whose sum is σ = 12172310. Its totient is φ = 12172308.

The previous prime is 12172283. The next prime is 12172327. The reversal of 12172309 is 90327121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11356900 + 815409 = 3370^2 + 903^2 .

It is a cyclic number.

It is not a de Polignac number, because 12172309 - 2¹¹ = 12170261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12172409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6086154 + 6086155.

It is an arithmetic number, because the mean of its divisors is an integer number (6086155).

Almost surely, 2^12172309 is an apocalyptic number.

It is an amenable number.

12172309 is a deficient number, since it is larger than the sum of its proper divisors (1).

12172309 is an equidigital number, since it uses as much as digits as its factorization.

12172309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 12172309 is about 3488.8836323386. The cubic root of 12172309 is about 230.0334481916.

The spelling of 12172309 in words is "twelve million, one hundred seventy-two thousand, three hundred nine".