12126516881 has 2 divisors, whose sum is σ = 12126516882. Its totient is φ = 12126516880.

The previous prime is 12126516841. The next prime is 12126516893. The reversal of 12126516881 is 18861562121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6230734225 + 5895782656 = 78935^2 + 76784^2 .

It is an emirp because it is prime and its reverse (18861562121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12126516881 - 2¹⁸ = 12126254737 is a prime.

It is a super-2 number, since 2×12126516881² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12126516811) 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, 6063258440 + 6063258441.

It is an arithmetic number, because the mean of its divisors is an integer number (6063258441).

Almost surely, 2^12126516881 is an apocalyptic number.

It is an amenable number.

12126516881 is a deficient number, since it is larger than the sum of its proper divisors (1).

12126516881 is an equidigital number, since it uses as much as digits as its factorization.

12126516881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46080, while the sum is 41.

The spelling of 12126516881 in words is "twelve billion, one hundred twenty-six million, five hundred sixteen thousand, eight hundred eighty-one".