221343220 has 96 divisors (see below), whose sum is σ = 547061760. Its totient is φ = 73664640.

The previous prime is 221343173. The next prime is 221343251. The reversal of 221343220 is 22343122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1048915 + ... + 1049125.

It is an arithmetic number, because the mean of its divisors is an integer number (5698560).

Almost surely, 2^221343220 is an apocalyptic number.

221343220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221343220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273530880).

221343220 is an abundant number, since it is smaller than the sum of its proper divisors (325718540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221343220 is a wasteful number, since it uses less digits than its factorization.

221343220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413 (or 411 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 221343220 is about 14877.6080066656. The cubic root of 221343220 is about 604.9071824460.

Adding to 221343220 its reverse (22343122), we get a palindrome (243686342).

The spelling of 221343220 in words is "two hundred twenty-one million, three hundred forty-three thousand, two hundred twenty".