21031333020121 has 2 divisors, whose sum is σ = 21031333020122. Its totient is φ = 21031333020120.

The previous prime is 21031333020091. The next prime is 21031333020169. The reversal of 21031333020121 is 12102033313012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17874385851721 + 3156947168400 = 4227811^2 + 1776780^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031333020121 - 2³¹ = 21029185536473 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21031333020092 and 21031333020101.

It is not a weakly prime, because it can be changed into another prime (21031333020521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515666510060 + 10515666510061.

It is an arithmetic number, because the mean of its divisors is an integer number (10515666510061).

Almost surely, 2^{21031333020121} is an apocalyptic number.

It is an amenable number.

21031333020121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031333020121 is an equidigital number, since it uses as much as digits as its factorization.

21031333020121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 21031333020121 its reverse (12102033313012), we get a palindrome (33133366333133).

The spelling of 21031333020121 in words is "twenty-one trillion, thirty-one billion, three hundred thirty-three million, twenty thousand, one hundred twenty-one".