221221120220 has 24 divisors (see below), whose sum is σ = 467159691600. Its totient is φ = 87994097792.

The previous prime is 221221120217. The next prime is 221221120229. The reversal of 221221120220 is 22021122122.

It is a happy number.

221221120220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221120229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30893225 + ... + 30900384.

It is an arithmetic number, because the mean of its divisors is an integer number (19464987150).

Almost surely, 2^221221120220 is an apocalyptic number.

221221120220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221120220 is an abundant number, since it is smaller than the sum of its proper divisors (245938571380).

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

221221120220 is a wasteful number, since it uses less digits than its factorization.

221221120220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61793797 (or 61793795 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 221221120220 its reverse (22021122122), we get a palindrome (243242242342).

The spelling of 221221120220 in words is "two hundred twenty-one billion, two hundred twenty-one million, one hundred twenty thousand, two hundred twenty".