221344220 has 48 divisors (see below), whose sum is σ = 478853760. Its totient is φ = 85893696.

The previous prime is 221344217. The next prime is 221344241. The reversal of 221344220 is 22443122.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221344192 and 221344201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139391 + ... + 140969.

It is an arithmetic number, because the mean of its divisors is an integer number (9976120).

Almost surely, 2^221344220 is an apocalyptic number.

221344220 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 221344220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (239426880).

221344220 is an abundant number, since it is smaller than the sum of its proper divisors (257509540).

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

221344220 is a wasteful number, since it uses less digits than its factorization.

221344220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1794 (or 1792 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 221344220 is about 14877.6416141807. The cubic root of 221344220 is about 604.9080934087.

Adding to 221344220 its reverse (22443122), we get a palindrome (243787342).

The spelling of 221344220 in words is "two hundred twenty-one million, three hundred forty-four thousand, two hundred twenty".