12212112181 has 2 divisors, whose sum is σ = 12212112182. Its totient is φ = 12212112180.

The previous prime is 12212112179. The next prime is 12212112233. The reversal of 12212112181 is 18121121221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11957422500 + 254689681 = 109350^2 + 15959^2 .

It is a cyclic number.

It is not a de Polignac number, because 12212112181 - 2¹ = 12212112179 is a prime.

It is a super-2 number, since 2×12212112181² (a number of 21 digits) contains 22 as substring.

Together with 12212112179, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12212112151) 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, 6106056090 + 6106056091.

It is an arithmetic number, because the mean of its divisors is an integer number (6106056091).

Almost surely, 2^12212112181 is an apocalyptic number.

It is an amenable number.

12212112181 is a deficient number, since it is larger than the sum of its proper divisors (1).

12212112181 is an equidigital number, since it uses as much as digits as its factorization.

12212112181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 128, while the sum is 22.

The spelling of 12212112181 in words is "twelve billion, two hundred twelve million, one hundred twelve thousand, one hundred eighty-one".