221221101220 has 24 divisors (see below), whose sum is σ = 530930643264. Its totient is φ = 75847234656.

The previous prime is 221221101209. The next prime is 221221101229. The reversal of 221221101220 is 22101122122.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 221221101194 and 221221101203.

It is not an unprimeable number, because it can be changed into a prime (221221101229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 790075222 + ... + 790075501.

It is an arithmetic number, because the mean of its divisors is an integer number (22122110136).

Almost surely, 2^221221101220 is an apocalyptic number.

221221101220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221221101220 is an abundant number, since it is smaller than the sum of its proper divisors (309709542044).

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

221221101220 is a wasteful number, since it uses less digits than its factorization.

221221101220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1580150739 (or 1580150737 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221221101220 its reverse (22101122122), we get a palindrome (243322223342).

The spelling of 221221101220 in words is "two hundred twenty-one billion, two hundred twenty-one million, one hundred one thousand, two hundred twenty".