1221111220122 has 24 divisors (see below), whose sum is σ = 2743731384576. Its totient is φ = 407037073212.

The previous prime is 1221111220099. The next prime is 1221111220123. The reversal of 1221111220122 is 2210221111221.

It is a super-2 number, since 2×1221111220122² (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 junction number, because it is equal to n+sod(n) for n = 1221111220095 and 1221111220104.

It is not an unprimeable number, because it can be changed into a prime (1221111220123) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1256286778 + ... + 1256287749.

It is an arithmetic number, because the mean of its divisors is an integer number (114322141024).

Almost surely, 2^{1221111220122} is an apocalyptic number.

1221111220122 is an abundant number, since it is smaller than the sum of its proper divisors (1522620164454).

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

1221111220122 is an equidigital number, since it uses as much as digits as its factorization.

1221111220122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2512574544 (or 2512574532 counting only the distinct ones).

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

Adding to 1221111220122 its reverse (2210221111221), we get a palindrome (3431332331343).

The spelling of 1221111220122 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, two hundred twenty thousand, one hundred twenty-two".