1221211011012 has 24 divisors (see below), whose sum is σ = 2885561884800. Its totient is φ = 401917547616.

The previous prime is 1221211011001. The next prime is 1221211011019. The reversal of 1221211011012 is 2101101121221.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1221211010982 and 1221211011000.

It is not an unprimeable number, because it can be changed into a prime (1221211011019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 644097687 + ... + 644099582.

It is an arithmetic number, because the mean of its divisors is an integer number (120231745200).

Almost surely, 2^{1221211011012} is an apocalyptic number.

1221211011012 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221211011012 is an abundant number, since it is smaller than the sum of its proper divisors (1664350873788).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221211011012 is a wasteful number, since it uses less digits than its factorization.

1221211011012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1288197355 (or 1288197353 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1221211011012 its reverse (2101101121221), we get a palindrome (3322312132233).

The spelling of 1221211011012 in words is "one trillion, two hundred twenty-one billion, two hundred eleven million, eleven thousand, twelve".