1221221210212 has 24 divisors (see below), whose sum is σ = 2158637644800. Its totient is φ = 604471727616.

The previous prime is 1221221210173. The next prime is 1221221210239. The reversal of 1221221210212 is 2120121221221.

It is a self number, because there is not a number n which added to its sum of digits gives 1221221210212.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 671364 + ... + 1700932.

It is an arithmetic number, because the mean of its divisors is an integer number (89943235200).

Almost surely, 2^{1221221210212} is an apocalyptic number.

It is an amenable number.

1221221210212 is a deficient number, since it is larger than the sum of its proper divisors (937416434588).

1221221210212 is a wasteful number, since it uses less digits than its factorization.

1221221210212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1032555 (or 1032553 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 1221221210212 its reverse (2120121221221), we get a palindrome (3341342431433).

The spelling of 1221221210212 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, two hundred ten thousand, two hundred twelve".