1220221200221 has 4 divisors (see below), whose sum is σ = 1220223486972. Its totient is φ = 1220218913472.

The previous prime is 1220221200199. The next prime is 1220221200239. The reversal of 1220221200221 is 1220021220221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 700652702500 + 519568497721 = 837050^2 + 720811^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220221200221 - 2¹⁸ = 1220220938077 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220221200221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220221700221) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 129035 + ... + 1567511.

It is an arithmetic number, because the mean of its divisors is an integer number (305055871743).

Almost surely, 2^{1220221200221} is an apocalyptic number.

It is an amenable number.

1220221200221 is a deficient number, since it is larger than the sum of its proper divisors (2286751).

1220221200221 is an equidigital number, since it uses as much as digits as its factorization.

1220221200221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2286750.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 1220221200221 its reverse (1220021220221), we get a palindrome (2440242420442).

The spelling of 1220221200221 in words is "one trillion, two hundred twenty billion, two hundred twenty-one million, two hundred thousand, two hundred twenty-one".