1221111110112 has 96 divisors (see below), whose sum is σ = 3294676425600. Its totient is φ = 395720022528.

The previous prime is 1221111110071. The next prime is 1221111110123. The reversal of 1221111110112 is 2110111111221.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×1221111110112² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221111110091 and 1221111110100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4335439 + ... + 4608497.

It is an arithmetic number, because the mean of its divisors is an integer number (34319546100).

Almost surely, 2^{1221111110112} is an apocalyptic number.

1221111110112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221111110112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1647338212800).

1221111110112 is an abundant number, since it is smaller than the sum of its proper divisors (2073565315488).

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

1221111110112 is a wasteful number, since it uses less digits than its factorization.

1221111110112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274368 (or 274360 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 1221111110112 its reverse (2110111111221), we get a palindrome (3331222221333).

The spelling of 1221111110112 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, one hundred ten thousand, one hundred twelve".