1221020222201 has 12 divisors (see below), whose sum is σ = 1399944525372. Its totient is φ = 1060795846656.

The previous prime is 1221020222179. The next prime is 1221020222209. The reversal of 1221020222201 is 1022220201221.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 30870138601 + 1190150083600 = 175699^2 + 1090940^2 .

It is not a de Polignac number, because 1221020222201 - 2¹⁴ = 1221020205817 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

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 1221020222201.

It is not an unprimeable number, because it can be changed into a prime (1221020222209) 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 11 ways as a sum of consecutive naturals, for example, 212496296 + ... + 212502041.

It is an arithmetic number, because the mean of its divisors is an integer number (116662043781).

Almost surely, 2^{1221020222201} is an apocalyptic number.

It is an amenable number.

1221020222201 is a deficient number, since it is larger than the sum of its proper divisors (178924303171).

1221020222201 is a wasteful number, since it uses less digits than its factorization.

1221020222201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424998380 (or 424998367 counting only the distinct ones).

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

Adding to 1221020222201 its reverse (1022220201221), we get a palindrome (2243240423422).

The spelling of 1221020222201 in words is "one trillion, two hundred twenty-one billion, twenty million, two hundred twenty-two thousand, two hundred one".