1220221121121 has 12 divisors (see below), whose sum is σ = 1767534659748. Its totient is φ = 811176267264.

The previous prime is 1220221121117. The next prime is 1220221121123. The reversal of 1220221121121 is 1211211220221.

1220221121121 is a `hidden beast` number, since 1 + 220 + 2 + 211 + 211 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 337869000225 + 882352120896 = 581265^2 + 939336^2 .

It is not a de Polignac number, because 1220221121121 - 2² = 1220221121117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1220221121094 and 1220221121103.

It is not an unprimeable number, because it can be changed into a prime (1220221121123) 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, 192036660 + ... + 192043013.

It is an arithmetic number, because the mean of its divisors is an integer number (147294554979).

Almost surely, 2^{1220221121121} is an apocalyptic number.

It is an amenable number.

1220221121121 is a deficient number, since it is larger than the sum of its proper divisors (547313538627).

1220221121121 is a wasteful number, since it uses less digits than its factorization.

1220221121121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384080032 (or 384080029 counting only the distinct ones).

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

Adding to 1220221121121 its reverse (1211211220221), we get a palindrome (2431432341342).

The spelling of 1220221121121 in words is "one trillion, two hundred twenty billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred twenty-one".