12231211211981 has 2 divisors, whose sum is σ = 12231211211982. Its totient is φ = 12231211211980.

The previous prime is 12231211211959. The next prime is 12231211212019. The reversal of 12231211211981 is 18911211213221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12209671246756 + 21539965225 = 3494234^2 + 146765^2 .

It is a cyclic number.

It is not a de Polignac number, because 12231211211981 - 2⁶ = 12231211211917 is a prime.

It is a super-2 number, since 2×12231211211981² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12231211211081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6115605605990 + 6115605605991.

It is an arithmetic number, because the mean of its divisors is an integer number (6115605605991).

Almost surely, 2^{12231211211981} is an apocalyptic number.

It is an amenable number.

12231211211981 is a deficient number, since it is larger than the sum of its proper divisors (1).

12231211211981 is an equidigital number, since it uses as much as digits as its factorization.

12231211211981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 35.

The spelling of 12231211211981 in words is "twelve trillion, two hundred thirty-one billion, two hundred eleven million, two hundred eleven thousand, nine hundred eighty-one".