213641221 has 2 divisors, whose sum is σ = 213641222. Its totient is φ = 213641220.

The previous prime is 213641213. The next prime is 213641237. The reversal of 213641221 is 122146312.

213641221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 210540100 + 3101121 = 14510^2 + 1761^2 .

It is a cyclic number.

It is not a de Polignac number, because 213641221 - 2³ = 213641213 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 213641192 and 213641201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213641291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106820610 + 106820611.

It is an arithmetic number, because the mean of its divisors is an integer number (106820611).

Almost surely, 2^213641221 is an apocalyptic number.

It is an amenable number.

213641221 is a deficient number, since it is larger than the sum of its proper divisors (1).

213641221 is an equidigital number, since it uses as much as digits as its factorization.

213641221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 22.

The square root of 213641221 is about 14616.4708804827. The cubic root of 213641221 is about 597.8079466265.

Adding to 213641221 its reverse (122146312), we get a palindrome (335787533).

The spelling of 213641221 in words is "two hundred thirteen million, six hundred forty-one thousand, two hundred twenty-one".