213231221221 has 8 divisors (see below), whose sum is σ = 233057274624. Its totient is φ = 194214394560.

The previous prime is 213231221183. The next prime is 213231221263. The reversal of 213231221221 is 122122132312.

213231221221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213231221221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 213231221192 and 213231221201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213231221521) 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 in 7 ways as a sum of consecutive naturals, for example, 202306135 + ... + 202307188.

It is an arithmetic number, because the mean of its divisors is an integer number (29132159328).

Almost surely, 2^213231221221 is an apocalyptic number.

It is an amenable number.

213231221221 is a deficient number, since it is larger than the sum of its proper divisors (19826053403).

213231221221 is a wasteful number, since it uses less digits than its factorization.

213231221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404613371.

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

Adding to 213231221221 its reverse (122122132312), we get a palindrome (335353353533).

The spelling of 213231221221 in words is "two hundred thirteen billion, two hundred thirty-one million, two hundred twenty-one thousand, two hundred twenty-one".