2120212121081 has 2 divisors, whose sum is σ = 2120212121082. Its totient is φ = 2120212121080.

The previous prime is 2120212121051. The next prime is 2120212121191. The reversal of 2120212121081 is 1801212120212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1607040471481 + 513171649600 = 1267691^2 + 716360^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120212121081 - 2¹⁰ = 2120212120057 is a prime.

It is a super-2 number, since 2×2120212121081² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2120212121051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060106060540 + 1060106060541.

It is an arithmetic number, because the mean of its divisors is an integer number (1060106060541).

Almost surely, 2^{2120212121081} is an apocalyptic number.

It is an amenable number.

2120212121081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2120212121081 is an equidigital number, since it uses as much as digits as its factorization.

2120212121081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 256, while the sum is 23.

Adding to 2120212121081 its reverse (1801212120212), we get a palindrome (3921424241293).

The spelling of 2120212121081 in words is "two trillion, one hundred twenty billion, two hundred twelve million, one hundred twenty-one thousand, eighty-one".