1221111110120 has 128 divisors (see below), whose sum is σ = 3047411738880. Its totient is φ = 436617216000.

The previous prime is 1221111110071. The next prime is 1221111110123. The reversal of 1221111110120 is 210111111221.

It is a super-2 number, since 2×1221111110120² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221111110095 and 1221111110104.

It is not an unprimeable number, because it can be changed into a prime (1221111110123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 113554664 + ... + 113565416.

It is an arithmetic number, because the mean of its divisors is an integer number (23807904210).

Almost surely, 2^{1221111110120} is an apocalyptic number.

1221111110120 is a gapful number since it is divisible by the number (10) 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 1221111110120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1523705869440).

1221111110120 is an abundant number, since it is smaller than the sum of its proper divisors (1826300628760).

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

1221111110120 is a wasteful number, since it uses less digits than its factorization.

1221111110120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15067 (or 15063 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 1221111110120 its reverse (210111111221), we get a palindrome (1431222221341).

The spelling of 1221111110120 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, one hundred ten thousand, one hundred twenty".