2121022021 has 2 divisors, whose sum is σ = 2121022022. Its totient is φ = 2121022020.

The previous prime is 2121021967. The next prime is 2121022061. The reversal of 2121022021 is 1202201212.

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., 2082096900 + 38925121 = 45630^2 + 6239^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121022021 - 2¹¹ = 2121019973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121021992 and 2121022010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121022061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060511010 + 1060511011.

It is an arithmetic number, because the mean of its divisors is an integer number (1060511011).

Almost surely, 2^2121022021 is an apocalyptic number.

It is an amenable number.

2121022021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121022021 is an equidigital number, since it uses as much as digits as its factorization.

2121022021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 2121022021 is about 46054.5548344569. The cubic root of 2121022021 is about 1284.8380585942.

Adding to 2121022021 its reverse (1202201212), we get a palindrome (3323223233).

The spelling of 2121022021 in words is "two billion, one hundred twenty-one million, twenty-two thousand, twenty-one".