1220222211221 has 8 divisors (see below), whose sum is σ = 1314135616920. Its totient is φ = 1126315971072.

The previous prime is 1220222211209. The next prime is 1220222211251. The reversal of 1220222211221 is 1221122220221.

It can be written as a sum of positive squares in 4 ways, for example, as 94978610596 + 1125243600625 = 308186^2 + 1060775^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1220222211221 - 2⁶ = 1220222211157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1220222211193 and 1220222211202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220222211251) 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 7 ways as a sum of consecutive naturals, for example, 1435076 + ... + 2121293.

It is an arithmetic number, because the mean of its divisors is an integer number (164266952115).

Almost surely, 2^{1220222211221} is an apocalyptic number.

It is an amenable number.

1220222211221 is a deficient number, since it is larger than the sum of its proper divisors (93913405699).

1220222211221 is a wasteful number, since it uses less digits than its factorization.

1220222211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3582775.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 1220222211221 its reverse (1221122220221), we get a palindrome (2441344431442).

The spelling of 1220222211221 in words is "one trillion, two hundred twenty billion, two hundred twenty-two million, two hundred eleven thousand, two hundred twenty-one".