21301220220121 has 4 divisors (see below), whose sum is σ = 21361563620532. Its totient is φ = 21240876819712.

The previous prime is 21301220220113. The next prime is 21301220220143. The reversal of 21301220220121 is 12102202210312.

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 11281235150025 + 10019985070096 = 3358755^2 + 3165436^2 .

It is a cyclic number.

It is not a de Polignac number, because 21301220220121 - 2³ = 21301220220113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21301220221121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30171699676 + ... + 30171700381.

It is an arithmetic number, because the mean of its divisors is an integer number (5340390905133).

Almost surely, 2^{21301220220121} is an apocalyptic number.

It is an amenable number.

21301220220121 is a deficient number, since it is larger than the sum of its proper divisors (60343400411).

21301220220121 is an equidigital number, since it uses as much as digits as its factorization.

21301220220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60343400410.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21301220220121 its reverse (12102202210312), we get a palindrome (33403422430433).

The spelling of 21301220220121 in words is "twenty-one trillion, three hundred one billion, two hundred twenty million, two hundred twenty thousand, one hundred twenty-one".