1221222122120 has 256 divisors, whose sum is σ = 3723146380800. Its totient is φ = 348135874560.

The previous prime is 1221222122117. The next prime is 1221222122177. The reversal of 1221222122120 is 212212221221.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1221222122092 and 1221222122101.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4224452 + ... + 4504268.

It is an arithmetic number, because the mean of its divisors is an integer number (14543540550).

Almost surely, 2^{1221222122120} is an apocalyptic number.

1221222122120 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 1221222122120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1861573190400).

1221222122120 is an abundant number, since it is smaller than the sum of its proper divisors (2501924258680).

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

1221222122120 is a wasteful number, since it uses less digits than its factorization.

1221222122120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279968 (or 279964 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 1221222122120 its reverse (212212221221), we get a palindrome (1433434343341).

The spelling of 1221222122120 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-two million, one hundred twenty-two thousand, one hundred twenty".