221222120 has 128 divisors (see below), whose sum is σ = 588211200. Its totient is φ = 73322496.

The previous prime is 221222087. The next prime is 221222123. The reversal of 221222120 is 21222122.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 221222095 and 221222104.

It is not an unprimeable number, because it can be changed into a prime (221222123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1614692 + ... + 1614828.

It is an arithmetic number, because the mean of its divisors is an integer number (4595400).

Almost surely, 2^221222120 is an apocalyptic number.

221222120 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 221222120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294105600).

221222120 is an abundant number, since it is smaller than the sum of its proper divisors (366989080).

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

221222120 is a wasteful number, since it uses less digits than its factorization.

221222120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 221222120 is about 14873.5375751702. The cubic root of 221222120 is about 604.7968445684.

Adding to 221222120 its reverse (21222122), we get a palindrome (242444242).

It can be divided in two parts, 22122 and 2120, that added together give a palindrome (24242).

The spelling of 221222120 in words is "two hundred twenty-one million, two hundred twenty-two thousand, one hundred twenty".