221232320 has 56 divisors (see below), whose sum is σ = 529285200. Its totient is φ = 88077312.

The previous prime is 221232283. The next prime is 221232343. The reversal of 221232320 is 23232122.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71771 + ... + 74789.

Almost surely, 2^221232320 is an apocalyptic number.

221232320 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 221232320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264642600).

221232320 is an abundant number, since it is smaller than the sum of its proper divisors (308052880).

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

221232320 is a wasteful number, since it uses less digits than its factorization.

221232320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3265 (or 3255 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 17.

The square root of 221232320 is about 14873.8804620718. The cubic root of 221232320 is about 604.8061396501.

Adding to 221232320 its reverse (23232122), we get a palindrome (244464442).

The spelling of 221232320 in words is "two hundred twenty-one million, two hundred thirty-two thousand, three hundred twenty".