1220211012121 has 4 divisors (see below), whose sum is σ = 1221068505472. Its totient is φ = 1219353518772.

The previous prime is 1220211012107. The next prime is 1220211012157. The reversal of 1220211012121 is 1212101120221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1220211012121 - 2¹⁵ = 1220210979353 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1220211012095 and 1220211012104.

It is not an unprimeable number, because it can be changed into a prime (1220211012191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 428744541 + ... + 428747386.

It is an arithmetic number, because the mean of its divisors is an integer number (305267126368).

Almost surely, 2^{1220211012121} is an apocalyptic number.

It is an amenable number.

1220211012121 is a deficient number, since it is larger than the sum of its proper divisors (857493351).

1220211012121 is an equidigital number, since it uses as much as digits as its factorization.

1220211012121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 857493350.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1220211012121 its reverse (1212101120221), we get a palindrome (2432312132342).

The spelling of 1220211012121 in words is "one trillion, two hundred twenty billion, two hundred eleven million, twelve thousand, one hundred twenty-one".