1221221110012 has 24 divisors (see below), whose sum is σ = 2194341855552. Its totient is φ = 594335404800.

The previous prime is 1221221110009. The next prime is 1221221110027. The reversal of 1221221110012 is 2100111221221.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8567913 + ... + 8709280.

It is an arithmetic number, because the mean of its divisors is an integer number (91430910648).

Almost surely, 2^{1221221110012} is an apocalyptic number.

It is an amenable number.

1221221110012 is a deficient number, since it is larger than the sum of its proper divisors (973120745540).

1221221110012 is a wasteful number, since it uses less digits than its factorization.

1221221110012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17277669 (or 17277667 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221221110012 its reverse (2100111221221), we get a palindrome (3321332331233).

The spelling of 1221221110012 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, one hundred ten thousand, twelve".