215213221021 has 2 divisors, whose sum is σ = 215213221022. Its totient is φ = 215213221020.

The previous prime is 215213221007. The next prime is 215213221033. The reversal of 215213221021 is 120122312512.

215213221021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139181224900 + 76031996121 = 373070^2 + 275739^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215213221021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 215213220983 and 215213221001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215213221001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107606610510 + 107606610511.

It is an arithmetic number, because the mean of its divisors is an integer number (107606610511).

Almost surely, 2^215213221021 is an apocalyptic number.

It is an amenable number.

215213221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

215213221021 is an equidigital number, since it uses as much as digits as its factorization.

215213221021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 22.

Adding to 215213221021 its reverse (120122312512), we get a palindrome (335335533533).

The spelling of 215213221021 in words is "two hundred fifteen billion, two hundred thirteen million, two hundred twenty-one thousand, twenty-one".