1212222181 has 2 divisors, whose sum is σ = 1212222182. Its totient is φ = 1212222180.

The previous prime is 1212222163. The next prime is 1212222191. The reversal of 1212222181 is 1812222121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 880071556 + 332150625 = 29666^2 + 18225^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212222181 - 2⁵ = 1212222149 is a prime.

It is a super-2 number, since 2×1212222181² = 2938965232216793522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212222191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606111090 + 606111091.

It is an arithmetic number, because the mean of its divisors is an integer number (606111091).

Almost surely, 2^1212222181 is an apocalyptic number.

It is an amenable number.

1212222181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212222181 is an equidigital number, since it uses as much as digits as its factorization.

1212222181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 256, while the sum is 22.

The square root of 1212222181 is about 34816.9812160675. The cubic root of 1212222181 is about 1066.2541687016.

The spelling of 1212222181 in words is "one billion, two hundred twelve million, two hundred twenty-two thousand, one hundred eighty-one".