12121102181 has 2 divisors, whose sum is σ = 12121102182. Its totient is φ = 12121102180.

The previous prime is 12121102163. The next prime is 12121102211. The reversal of 12121102181 is 18120112121.

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., 8810825956 + 3310276225 = 93866^2 + 57535^2 .

It is an emirp because it is prime and its reverse (18120112121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12121102181 - 2²² = 12116907877 is a prime.

It is a super-4 number, since 4×12121102181⁴ (a number of 41 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12121102111) 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, 6060551090 + 6060551091.

It is an arithmetic number, because the mean of its divisors is an integer number (6060551091).

Almost surely, 2^12121102181 is an apocalyptic number.

It is an amenable number.

12121102181 is a deficient number, since it is larger than the sum of its proper divisors (1).

12121102181 is an equidigital number, since it uses as much as digits as its factorization.

12121102181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 20.

The spelling of 12121102181 in words is "twelve billion, one hundred twenty-one million, one hundred two thousand, one hundred eighty-one".