213322561 has 2 divisors, whose sum is σ = 213322562. Its totient is φ = 213322560.

The previous prime is 213322523. The next prime is 213322567. The reversal of 213322561 is 165223312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 149817600 + 63504961 = 12240^2 + 7969^2 .

It is a cyclic number.

It is not a de Polignac number, because 213322561 - 2¹⁹ = 212798273 is a prime.

It is not a weakly prime, because it can be changed into another prime (213322567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106661280 + 106661281.

It is an arithmetic number, because the mean of its divisors is an integer number (106661281).

Almost surely, 2^213322561 is an apocalyptic number.

It is an amenable number.

213322561 is a deficient number, since it is larger than the sum of its proper divisors (1).

213322561 is an equidigital number, since it uses as much as digits as its factorization.

213322561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 25.

The square root of 213322561 is about 14605.5660965264. The cubic root of 213322561 is about 597.5105753746.

Adding to 213322561 its reverse (165223312), we get a palindrome (378545873).

The spelling of 213322561 in words is "two hundred thirteen million, three hundred twenty-two thousand, five hundred sixty-one".