1221120222102 has 144 divisors (see below), whose sum is σ = 2988287798496. Its totient is φ = 359849952000.

The previous prime is 1221120222089. The next prime is 1221120222107. The reversal of 1221120222102 is 2012220211221.

It is a happy number.

1221120222102 is a `hidden beast` number, since 1 + 221 + 120 + 222 + 102 = 666.

It is a super-2 number, since 2×1221120222102² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221120222107) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 290671602 + ... + 290675802.

Almost surely, 2^{1221120222102} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221120222102, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1494143899248).

1221120222102 is an abundant number, since it is smaller than the sum of its proper divisors (1767167576394).

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

1221120222102 is a wasteful number, since it uses less digits than its factorization.

1221120222102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7875 (or 7861 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 1221120222102 its reverse (2012220211221), we get a palindrome (3233340433323).

The spelling of 1221120222102 in words is "one trillion, two hundred twenty-one billion, one hundred twenty million, two hundred twenty-two thousand, one hundred two".