1212220221101 has 4 divisors (see below), whose sum is σ = 1232092683804. Its totient is φ = 1192347758400.

The previous prime is 1212220221071. The next prime is 1212220221103. The reversal of 1212220221101 is 1011220222121.

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 395356743076 + 816863478025 = 628774^2 + 903805^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212220221101 - 2²² = 1212216026797 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 1212220221101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212220221103) 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, 9936231260 + ... + 9936231381.

It is an arithmetic number, because the mean of its divisors is an integer number (308023170951).

Almost surely, 2^{1212220221101} is an apocalyptic number.

It is an amenable number.

1212220221101 is a deficient number, since it is larger than the sum of its proper divisors (19872462703).

1212220221101 is an equidigital number, since it uses as much as digits as its factorization.

1212220221101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19872462702.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 1212220221101 its reverse (1011220222121), we get a palindrome (2223440443222).

The spelling of 1212220221101 in words is "one trillion, two hundred twelve billion, two hundred twenty million, two hundred twenty-one thousand, one hundred one".