221213231220 has 96 divisors (see below), whose sum is σ = 624414510720. Its totient is φ = 58512762880.

The previous prime is 221213231047. The next prime is 221213231233. The reversal of 221213231220 is 22132312122.

221213231220 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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, 21444784 + ... + 21455096.

It is an arithmetic number, because the mean of its divisors is an integer number (6504317820).

Almost surely, 2^221213231220 is an apocalyptic number.

221213231220 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 221213231220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312207255360).

221213231220 is an abundant number, since it is smaller than the sum of its proper divisors (403201279500).

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

221213231220 is a wasteful number, since it uses less digits than its factorization.

221213231220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13185 (or 13183 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 221213231220 its reverse (22132312122), we get a palindrome (243345543342).

The spelling of 221213231220 in words is "two hundred twenty-one billion, two hundred thirteen million, two hundred thirty-one thousand, two hundred twenty".