201221220220 has 24 divisors (see below), whose sum is σ = 422582567904. Its totient is φ = 80485058496.

The previous prime is 201221220191. The next prime is 201221220253. The reversal of 201221220220 is 22022122102.

It is a junction number, because it is equal to n+sod(n) for n = 201221220194 and 201221220203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 296449 + ... + 700231.

It is an arithmetic number, because the mean of its divisors is an integer number (17607606996).

Almost surely, 2^201221220220 is an apocalyptic number.

201221220220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201221220220 is an abundant number, since it is smaller than the sum of its proper divisors (221361347684).

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

201221220220 is a wasteful number, since it uses less digits than its factorization.

201221220220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 428709 (or 428707 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 201221220220 its reverse (22022122102), we get a palindrome (223243342322).

The spelling of 201221220220 in words is "two hundred one billion, two hundred twenty-one million, two hundred twenty thousand, two hundred twenty".