1218365243 has 2 divisors, whose sum is σ = 1218365244. Its totient is φ = 1218365242.

The previous prime is 1218365153. The next prime is 1218365251. The reversal of 1218365243 is 3425638121.

It is a strong prime.

It is an emirp because it is prime and its reverse (3425638121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1218365243 - 2¹⁸ = 1218103099 is a prime.

It is not a weakly prime, because it can be changed into another prime (1218365263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 609182621 + 609182622.

It is an arithmetic number, because the mean of its divisors is an integer number (609182622).

Almost surely, 2^1218365243 is an apocalyptic number.

1218365243 is a deficient number, since it is larger than the sum of its proper divisors (1).

1218365243 is an equidigital number, since it uses as much as digits as its factorization.

1218365243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 35.

The square root of 1218365243 is about 34905.0890702201. The cubic root of 1218365243 is about 1068.0522527587.

The spelling of 1218365243 in words is "one billion, two hundred eighteen million, three hundred sixty-five thousand, two hundred forty-three".