213433021 has 2 divisors, whose sum is σ = 213433022. Its totient is φ = 213433020.

The previous prime is 213433013. The next prime is 213433027. The reversal of 213433021 is 120334312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 202635225 + 10797796 = 14235^2 + 3286^2 .

It is a cyclic number.

It is not a de Polignac number, because 213433021 - 2³ = 213433013 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 213433021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213433027) 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, 106716510 + 106716511.

It is an arithmetic number, because the mean of its divisors is an integer number (106716511).

Almost surely, 2^213433021 is an apocalyptic number.

It is an amenable number.

213433021 is a deficient number, since it is larger than the sum of its proper divisors (1).

213433021 is an equidigital number, since it uses as much as digits as its factorization.

213433021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 213433021 is about 14609.3470422192. The cubic root of 213433021 is about 597.6136893775.

Adding to 213433021 its reverse (120334312), we get a palindrome (333767333).

The spelling of 213433021 in words is "two hundred thirteen million, four hundred thirty-three thousand, twenty-one".