21120301021 has 2 divisors, whose sum is σ = 21120301022. Its totient is φ = 21120301020.

The previous prime is 21120301019. The next prime is 21120301049. The reversal of 21120301021 is 12010302112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14865705625 + 6254595396 = 121925^2 + 79086^2 .

It is a cyclic number.

It is not a de Polignac number, because 21120301021 - 2¹ = 21120301019 is a prime.

Together with 21120301019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21120300992 and 21120301010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21120301051) 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, 10560150510 + 10560150511.

It is an arithmetic number, because the mean of its divisors is an integer number (10560150511).

Almost surely, 2^21120301021 is an apocalyptic number.

It is an amenable number.

21120301021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120301021 is an equidigital number, since it uses as much as digits as its factorization.

21120301021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21120301021 its reverse (12010302112), we get a palindrome (33130603133).

The spelling of 21120301021 in words is "twenty-one billion, one hundred twenty million, three hundred one thousand, twenty-one".