20102221011221 has 4 divisors (see below), whose sum is σ = 20115794423244. Its totient is φ = 20088647599200.

The previous prime is 20102221011217. The next prime is 20102221011307. The reversal of 20102221011221 is 12211012220102.

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 6122586076996 + 13979634934225 = 2474386^2 + 3738935^2 .

It is a cyclic number.

It is not a de Polignac number, because 20102221011221 - 2² = 20102221011217 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 20102221011221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20102221011721) 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, 6786703790 + ... + 6786706751.

It is an arithmetic number, because the mean of its divisors is an integer number (5028948605811).

Almost surely, 2^{20102221011221} is an apocalyptic number.

It is an amenable number.

20102221011221 is a deficient number, since it is larger than the sum of its proper divisors (13573412023).

20102221011221 is a wasteful number, since it uses less digits than its factorization.

20102221011221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13573412022.

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

Adding to 20102221011221 its reverse (12211012220102), we get a palindrome (32313233231323).

The spelling of 20102221011221 in words is "twenty trillion, one hundred two billion, two hundred twenty-one million, eleven thousand, two hundred twenty-one".