1221220121022 has 48 divisors (see below), whose sum is σ = 2921297678208. Its totient is φ = 365608063440.

The previous prime is 1221220121003. The next prime is 1221220121039. The reversal of 1221220121022 is 2201210221221.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 1221220120986 and 1221220121004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 37138858 + ... + 37171725.

It is an arithmetic number, because the mean of its divisors is an integer number (60860368296).

Almost surely, 2^{1221220121022} is an apocalyptic number.

1221220121022 is an abundant number, since it is smaller than the sum of its proper divisors (1700077557186).

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

1221220121022 is a wasteful number, since it uses less digits than its factorization.

1221220121022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74310685 (or 74310682 counting only the distinct ones).

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

Adding to 1221220121022 its reverse (2201210221221), we get a palindrome (3422430342243).

It can be divided in two parts, 1221 and 220121022, that multiplied together give a palindrome (268767767862).

The spelling of 1221220121022 in words is "one trillion, two hundred twenty-one billion, two hundred twenty million, one hundred twenty-one thousand, twenty-two".