12311261 has 2 divisors, whose sum is σ = 12311262. Its totient is φ = 12311260.

The previous prime is 12311251. The next prime is 12311267. The reversal of 12311261 is 16211321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11323225 + 988036 = 3365^2 + 994^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12311261 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12311267) 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, 6155630 + 6155631.

It is an arithmetic number, because the mean of its divisors is an integer number (6155631).

Almost surely, 2^12311261 is an apocalyptic number.

It is an amenable number.

12311261 is a deficient number, since it is larger than the sum of its proper divisors (1).

12311261 is an equidigital number, since it uses as much as digits as its factorization.

12311261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72, while the sum is 17.

The square root of 12311261 is about 3508.7406572729. The cubic root of 12311261 is about 230.9054478324.

Adding to 12311261 its reverse (16211321), we get a palindrome (28522582).

The spelling of 12311261 in words is "twelve million, three hundred eleven thousand, two hundred sixty-one".