12213809 has 2 divisors, whose sum is σ = 12213810. Its totient is φ = 12213808.

The previous prime is 12213793. The next prime is 12213821. The reversal of 12213809 is 90831221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9168784 + 3045025 = 3028^2 + 1745^2 .

It is a cyclic number.

It is not a de Polignac number, because 12213809 - 2⁴ = 12213793 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (12213109) 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, 6106904 + 6106905.

It is an arithmetic number, because the mean of its divisors is an integer number (6106905).

Almost surely, 2^12213809 is an apocalyptic number.

It is an amenable number.

12213809 is a deficient number, since it is larger than the sum of its proper divisors (1).

12213809 is an equidigital number, since it uses as much as digits as its factorization.

12213809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 12213809 is about 3494.8260328663. The cubic root of 12213809 is about 230.2945752991.

It can be divided in two parts, 122 and 13809, that added together give a palindrome (13931).

The spelling of 12213809 in words is "twelve million, two hundred thirteen thousand, eight hundred nine".