20212102212221 has 8 divisors (see below), whose sum is σ = 20216296822104. Its totient is φ = 20207907860800.

The previous prime is 20212102212199. The next prime is 20212102212227. The reversal of 20212102212221 is 12221220121202.

It can be written as a sum of positive squares in 4 ways, for example, as 12596695225 + 20199505516996 = 112235^2 + 4494386^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20212102212221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20212102212193 and 20212102212202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20212102212227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252924371 + ... + 253004271.

It is an arithmetic number, because the mean of its divisors is an integer number (2527037102763).

Almost surely, 2^{20212102212221} is an apocalyptic number.

It is an amenable number.

20212102212221 is a deficient number, since it is larger than the sum of its proper divisors (4194609883).

20212102212221 is an equidigital number, since it uses as much as digits as its factorization.

20212102212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129231.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 20212102212221 its reverse (12221220121202), we get a palindrome (32433322333423).

The spelling of 20212102212221 in words is "twenty trillion, two hundred twelve billion, one hundred two million, two hundred twelve thousand, two hundred twenty-one".