1211121012222 has 160 divisors (see below), whose sum is σ = 3091069175040. Its totient is φ = 350841300480.

The previous prime is 1211121012191. The next prime is 1211121012239. The reversal of 1211121012222 is 2222101211121.

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 = 1211121012195 and 1211121012204.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 77414733 + ... + 77430375.

It is an arithmetic number, because the mean of its divisors is an integer number (19319182344).

Almost surely, 2^{1211121012222} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211121012222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1545534587520).

1211121012222 is an abundant number, since it is smaller than the sum of its proper divisors (1879948162818).

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

1211121012222 is a wasteful number, since it uses less digits than its factorization.

1211121012222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17580 (or 17571 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1211121012222 its reverse (2222101211121), we get a palindrome (3433222223343).

The spelling of 1211121012222 in words is "one trillion, two hundred eleven billion, one hundred twenty-one million, twelve thousand, two hundred twenty-two".