12196511981 has 2 divisors, whose sum is σ = 12196511982. Its totient is φ = 12196511980.

The previous prime is 12196511947. The next prime is 12196511993. The reversal of 12196511981 is 18911569121.

12196511981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11653202500 + 543309481 = 107950^2 + 23309^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12196511981 is a prime.

It is a super-2 number, since 2×12196511981² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12196511081) 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, 6098255990 + 6098255991.

It is an arithmetic number, because the mean of its divisors is an integer number (6098255991).

Almost surely, 2^12196511981 is an apocalyptic number.

It is an amenable number.

12196511981 is a deficient number, since it is larger than the sum of its proper divisors (1).

12196511981 is an equidigital number, since it uses as much as digits as its factorization.

12196511981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 44.

The spelling of 12196511981 in words is "twelve billion, one hundred ninety-six million, five hundred eleven thousand, nine hundred eighty-one".