20002221121 has 2 divisors, whose sum is σ = 20002221122. Its totient is φ = 20002221120.

The previous prime is 20002221103. The next prime is 20002221133. The reversal of 20002221121 is 12112220002.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13980461121 + 6021760000 = 118239^2 + 77600^2 .

It is a cyclic number.

It is not a de Polignac number, because 20002221121 - 2⁷ = 20002220993 is a prime.

It is not a weakly prime, because it can be changed into another prime (20002221521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10001110560 + 10001110561.

It is an arithmetic number, because the mean of its divisors is an integer number (10001110561).

Almost surely, 2^20002221121 is an apocalyptic number.

It is an amenable number.

20002221121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20002221121 is an equidigital number, since it uses as much as digits as its factorization.

20002221121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20002221121 its reverse (12112220002), we get a palindrome (32114441123).

The spelling of 20002221121 in words is "twenty billion, two million, two hundred twenty-one thousand, one hundred twenty-one".