2121002000081 has 2 divisors, whose sum is σ = 2121002000082. Its totient is φ = 2121002000080.

The previous prime is 2121001999867. The next prime is 2121002000111. The reversal of 2121002000081 is 1800002001212.

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., 2119703046400 + 1298953681 = 1455920^2 + 36041^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121002000081 - 2¹⁰ = 2121001999057 is a prime.

It is a super-2 number, since 2×2121002000081² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2121002000281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060501000040 + 1060501000041.

It is an arithmetic number, because the mean of its divisors is an integer number (1060501000041).

Almost surely, 2^{2121002000081} is an apocalyptic number.

It is an amenable number.

2121002000081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121002000081 is an equidigital number, since it uses as much as digits as its factorization.

2121002000081 is an odious number, because the sum of its binary digits is odd.

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

Adding to 2121002000081 its reverse (1800002001212), we get a palindrome (3921004001293).

The spelling of 2121002000081 in words is "two trillion, one hundred twenty-one billion, two million, eighty-one", and thus it is an aban number.