2120021212121 has 2 divisors, whose sum is σ = 2120021212122. Its totient is φ = 2120021212120.

The previous prime is 2120021212109. The next prime is 2120021212123. The reversal of 2120021212121 is 1212121200212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1420063088896 + 699958123225 = 1191664^2 + 836635^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120021212121 - 2³⁴ = 2102841342937 is a prime.

Together with 2120021212123, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2120021212121.

It is not a weakly prime, because it can be changed into another prime (2120021212123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060010606060 + 1060010606061.

It is an arithmetic number, because the mean of its divisors is an integer number (1060010606061).

Almost surely, 2^{2120021212121} is an apocalyptic number.

It is an amenable number.

2120021212121 is a deficient number, since it is larger than the sum of its proper divisors (1).

2120021212121 is an equidigital number, since it uses as much as digits as its factorization.

2120021212121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 2120021212121 its reverse (1212121200212), we get a palindrome (3332142412333).

It can be divided in two parts, 21200212 and 12121, that multiplied together give a palindrome (256967769652).

The spelling of 2120021212121 in words is "two trillion, one hundred twenty billion, twenty-one million, two hundred twelve thousand, one hundred twenty-one".