213442221 has 8 divisors (see below), whose sum is σ = 284658304. Its totient is φ = 142260480.

The previous prime is 213442217. The next prime is 213442237. The reversal of 213442221 is 122244312.

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

It is not a de Polignac number, because 213442221 - 2² = 213442217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213446221) 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 in 7 ways as a sum of consecutive naturals, for example, 15885 + ... + 26061.

It is an arithmetic number, because the mean of its divisors is an integer number (35582288).

Almost surely, 2^213442221 is an apocalyptic number.

It is an amenable number.

213442221 is a deficient number, since it is larger than the sum of its proper divisors (71216083).

213442221 is a wasteful number, since it uses less digits than its factorization.

213442221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17171.

The product of its digits is 768, while the sum is 21.

The square root of 213442221 is about 14609.6619057390. The cubic root of 213442221 is about 597.6222759385.

Adding to 213442221 its reverse (122244312), we get a palindrome (335686533).

The spelling of 213442221 in words is "two hundred thirteen million, four hundred forty-two thousand, two hundred twenty-one".