221221201220 has 48 divisors (see below), whose sum is σ = 467074460160. Its totient is φ = 88010692224.

The previous prime is 221221201219. The next prime is 221221201241. The reversal of 221221201220 is 22102122122.

It is a happy number.

221221201220 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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, 15433697 + ... + 15448023.

It is an arithmetic number, because the mean of its divisors is an integer number (9730717920).

Almost surely, 2^221221201220 is an apocalyptic number.

221221201220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221201220 is an abundant number, since it is smaller than the sum of its proper divisors (245853258940).

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

221221201220 is a wasteful number, since it uses less digits than its factorization.

221221201220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18452 (or 18450 counting only the distinct ones).

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

Adding to 221221201220 its reverse (22102122122), we get a palindrome (243323323342).

The spelling of 221221201220 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred one thousand, two hundred twenty".