221211220220 has 24 divisors (see below), whose sum is σ = 484741109664. Its totient is φ = 84637336256.

The previous prime is 221211220213. The next prime is 221211220247. The reversal of 221211220220 is 22022112122.

It is a happy number.

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, 240446519 + ... + 240447438.

It is an arithmetic number, because the mean of its divisors is an integer number (20197546236).

Almost surely, 2^221211220220 is an apocalyptic number.

221211220220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221211220220 is an abundant number, since it is smaller than the sum of its proper divisors (263529889444).

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

221211220220 is a wasteful number, since it uses less digits than its factorization.

221211220220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480893989 (or 480893987 counting only the distinct ones).

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

Adding to 221211220220 its reverse (22022112122), we get a palindrome (243233332342).

The spelling of 221211220220 in words is "two hundred twenty-one billion, two hundred eleven million, two hundred twenty thousand, two hundred twenty".