1266123211 has 2 divisors, whose sum is σ = 1266123212. Its totient is φ = 1266123210.

The previous prime is 1266123149. The next prime is 1266123223. The reversal of 1266123211 is 1123216621.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1123216621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1266123211 - 2¹¹ = 1266121163 is a prime.

It is not a weakly prime, because it can be changed into another prime (1266123241) 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, 633061605 + 633061606.

It is an arithmetic number, because the mean of its divisors is an integer number (633061606).

Almost surely, 2^1266123211 is an apocalyptic number.

1266123211 is a deficient number, since it is larger than the sum of its proper divisors (1).

1266123211 is an equidigital number, since it uses as much as digits as its factorization.

1266123211 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 25.

The square root of 1266123211 is about 35582.6251280031. The cubic root of 1266123211 is about 1081.8290938464.

Adding to 1266123211 its reverse (1123216621), we get a palindrome (2389339832).

The spelling of 1266123211 in words is "one billion, two hundred sixty-six million, one hundred twenty-three thousand, two hundred eleven".