1221220122212 has 12 divisors (see below), whose sum is σ = 2150747541180. Its totient is φ = 606720824736.

The previous prime is 1221220122193. The next prime is 1221220122217. The reversal of 1221220122212 is 2122210221221.

It can be written as a sum of positive squares in 2 ways, for example, as 795938759716 + 425281362496 = 892154^2 + 652136^2 .

It is not an unprimeable number, because it can be changed into a prime (1221220122217) 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 in 3 ways as a sum of consecutive naturals, for example, 972308387 + ... + 972309642.

It is an arithmetic number, because the mean of its divisors is an integer number (179228961765).

Almost surely, 2^{1221220122212} is an apocalyptic number.

It is an amenable number.

1221220122212 is a deficient number, since it is larger than the sum of its proper divisors (929527418968).

1221220122212 is a wasteful number, since it uses less digits than its factorization.

1221220122212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1944618190 (or 1944618188 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 1221220122212 its reverse (2122210221221), we get a palindrome (3343430343433).

Subtracting 1221220122212 from its reverse (2122210221221), we obtain a palindrome (900990099009).

The spelling of 1221220122212 in words is "one trillion, two hundred twenty-one billion, two hundred twenty million, one hundred twenty-two thousand, two hundred twelve".