121222100220 has 96 divisors (see below), whose sum is σ = 366123233280. Its totient is φ = 29790961920.

The previous prime is 121222100191. The next prime is 121222100221. The reversal of 121222100220 is 22001222121.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 121222100220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121222100221) 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, 357285 + ... + 608355.

It is an arithmetic number, because the mean of its divisors is an integer number (3813783680).

Almost surely, 2^121222100220 is an apocalyptic number.

121222100220 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 121222100220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183061616640).

121222100220 is an abundant number, since it is smaller than the sum of its proper divisors (244901133060).

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

121222100220 is a wasteful number, since it uses less digits than its factorization.

121222100220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251715 (or 251713 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 121222100220 its reverse (22001222121), we get a palindrome (143223322341).

The spelling of 121222100220 in words is "one hundred twenty-one billion, two hundred twenty-two million, one hundred thousand, two hundred twenty".