20202111021221 has 4 divisors (see below), whose sum is σ = 20205968599692. Its totient is φ = 20198253442752.

The previous prime is 20202111021203. The next prime is 20202111021227. The reversal of 20202111021221 is 12212011120202.

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 18753108996196 + 1449002025025 = 4330486^2 + 1203745^2 .

It is a cyclic number.

It is not a de Polignac number, because 20202111021221 - 2¹⁴ = 20202111004837 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 20202111021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20202111021227) 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, 1928781380 + ... + 1928791853.

It is an arithmetic number, because the mean of its divisors is an integer number (5051492149923).

Almost surely, 2^{20202111021221} is an apocalyptic number.

It is an amenable number.

20202111021221 is a deficient number, since it is larger than the sum of its proper divisors (3857578471).

20202111021221 is an equidigital number, since it uses as much as digits as its factorization.

20202111021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3857578470.

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

Adding to 20202111021221 its reverse (12212011120202), we get a palindrome (32414122141423).

The spelling of 20202111021221 in words is "twenty trillion, two hundred two billion, one hundred eleven million, twenty-one thousand, two hundred twenty-one".