213331221 has 24 divisors (see below), whose sum is σ = 335556000. Its totient is φ = 130086432.

The previous prime is 213331219. The next prime is 213331229. The reversal of 213331221 is 122133312.

It is not a de Polignac number, because 213331221 - 2¹ = 213331219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 213331194 and 213331203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213331229) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16551 + ... + 26468.

It is an arithmetic number, because the mean of its divisors is an integer number (13981500).

Almost surely, 2^213331221 is an apocalyptic number.

It is an amenable number.

213331221 is a deficient number, since it is larger than the sum of its proper divisors (122224779).

213331221 is a wasteful number, since it uses less digits than its factorization.

213331221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43073 (or 43070 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 213331221 is about 14605.8625558370. The cubic root of 213331221 is about 597.5186607385.

Adding to 213331221 its reverse (122133312), we get a palindrome (335464533).

The spelling of 213331221 in words is "two hundred thirteen million, three hundred thirty-one thousand, two hundred twenty-one".