20021100120121 has 2 divisors, whose sum is σ = 20021100120122. Its totient is φ = 20021100120120.

The previous prime is 20021100120103. The next prime is 20021100120143. The reversal of 20021100120121 is 12102100112002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19590848084025 + 430252036096 = 4426155^2 + 655936^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20021100120121 is a prime.

It is not a weakly prime, because it can be changed into another prime (20021100120181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010550060060 + 10010550060061.

It is an arithmetic number, because the mean of its divisors is an integer number (10010550060061).

Almost surely, 2^{20021100120121} is an apocalyptic number.

It is an amenable number.

20021100120121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20021100120121 is an equidigital number, since it uses as much as digits as its factorization.

20021100120121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20021100120121 its reverse (12102100112002), we get a palindrome (32123200232123).

The spelling of 20021100120121 in words is "twenty trillion, twenty-one billion, one hundred million, one hundred twenty thousand, one hundred twenty-one".