20012220121221 has 10 divisors (see below), whose sum is σ = 29894797958982. Its totient is φ = 13341480080760.

The previous prime is 20012220121213. The next prime is 20012220121277. The reversal of 20012220121221 is 12212102221002.

It is a happy number.

20012220121221 is a `hidden beast` number, since 200 + 1 + 2 + 220 + 1 + 21 + 221 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11442321022500 + 8569899098721 = 3382650^2 + 2927439^2 .

It is not a de Polignac number, because 20012220121221 - 2³ = 20012220121213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20012220121194 and 20012220121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20012220121121) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 123532222890 + ... + 123532223051.

Almost surely, 2^{20012220121221} is an apocalyptic number.

It is an amenable number.

20012220121221 is a deficient number, since it is larger than the sum of its proper divisors (9882577837761).

20012220121221 is an equidigital number, since it uses as much as digits as its factorization.

20012220121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247064445953 (or 247064445944 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 20012220121221 its reverse (12212102221002), we get a palindrome (32224322342223).

The spelling of 20012220121221 in words is "twenty trillion, twelve billion, two hundred twenty million, one hundred twenty-one thousand, two hundred twenty-one".