221333121 has 16 divisors (see below), whose sum is σ = 331588800. Its totient is φ = 145895904.

The previous prime is 221333089. The next prime is 221333143. The reversal of 221333121 is 121333122.

It is not a de Polignac number, because 221333121 - 2⁵ = 221333089 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 221333094 and 221333103.

It is not an unprimeable number, because it can be changed into a prime (221333171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43651 + ... + 48456.

It is an arithmetic number, because the mean of its divisors is an integer number (20724300).

Almost surely, 2^221333121 is an apocalyptic number.

It is an amenable number.

221333121 is a deficient number, since it is larger than the sum of its proper divisors (110255679).

221333121 is an equidigital number, since it uses as much as digits as its factorization.

221333121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92205 (or 92199 counting only the distinct ones).

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

The square root of 221333121 is about 14877.2686001161. The cubic root of 221333121 is about 604.8979824796.

Adding to 221333121 its reverse (121333122), we get a palindrome (342666243).

Subtracting from 221333121 its reverse (121333122), we obtain a palindrome (99999999).

The spelling of 221333121 in words is "two hundred twenty-one million, three hundred thirty-three thousand, one hundred twenty-one".