221113221 has 16 divisors (see below), whose sum is σ = 346041984. Its totient is φ = 122935104.

The previous prime is 221113213. The next prime is 221113231. The reversal of 221113221 is 122311122.

It is not a de Polignac number, because 221113221 - 2³ = 221113213 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 221113221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221113201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141510 + ... + 143063.

It is an arithmetic number, because the mean of its divisors is an integer number (21627624).

Almost surely, 2^221113221 is an apocalyptic number.

221113221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221113221 is a deficient number, since it is larger than the sum of its proper divisors (124928763).

221113221 is a wasteful number, since it uses less digits than its factorization.

221113221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284620.

The product of its digits is 48, while the sum is 15.

The square root of 221113221 is about 14869.8762940382. The cubic root of 221113221 is about 604.6975890003.

Adding to 221113221 its reverse (122311122), we get a palindrome (343424343).

The spelling of 221113221 in words is "two hundred twenty-one million, one hundred thirteen thousand, two hundred twenty-one".