20202102221221 has 4 divisors (see below), whose sum is σ = 21265370759200. Its totient is φ = 19138833683244.

The previous prime is 20202102221209. The next prime is 20202102221227. The reversal of 20202102221221 is 12212220120202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20202102221221 - 2²¹ = 20202100124069 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 1063268537959 = 20202102221221 / (2 + 0 + 2 + 0 + 2 + 1 + 0 + 2 + 2 + 2 + 1 + 2 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20202102221227) 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, 531634268961 + ... + 531634268998.

It is an arithmetic number, because the mean of its divisors is an integer number (5316342689800).

Almost surely, 2^{20202102221221} is an apocalyptic number.

It is an amenable number.

20202102221221 is a deficient number, since it is larger than the sum of its proper divisors (1063268537979).

20202102221221 is a wasteful number, since it uses less digits than its factorization.

20202102221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1063268537978.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 20202102221221 its reverse (12212220120202), we get a palindrome (32414322341423).

The spelling of 20202102221221 in words is "twenty trillion, two hundred two billion, one hundred two million, two hundred twenty-one thousand, two hundred twenty-one".