1311230909 has 2 divisors, whose sum is σ = 1311230910. Its totient is φ = 1311230908.

The previous prime is 1311230903. The next prime is 1311230933. The reversal of 1311230909 is 9090321131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 711715684 + 599515225 = 26678^2 + 24485^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1311230909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1311230903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655615454 + 655615455.

It is an arithmetic number, because the mean of its divisors is an integer number (655615455).

Almost surely, 2^1311230909 is an apocalyptic number.

It is an amenable number.

1311230909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311230909 is an equidigital number, since it uses as much as digits as its factorization.

1311230909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1458, while the sum is 29.

The square root of 1311230909 is about 36210.9225096517. The cubic root of 1311230909 is about 1094.5267817540.

The spelling of 1311230909 in words is "one billion, three hundred eleven million, two hundred thirty thousand, nine hundred nine".