221221221222 has 16 divisors (see below), whose sum is σ = 453233722032. Its totient is φ = 71941860480.

The previous prime is 221221221139. The next prime is 221221221223. The reversal of 221221221222 is 222122122122.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221221223) 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, 449636383 + ... + 449636874.

It is an arithmetic number, because the mean of its divisors is an integer number (28327107627).

Almost surely, 2^221221221222 is an apocalyptic number.

221221221222 is an abundant number, since it is smaller than the sum of its proper divisors (232012500810).

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

221221221222 is a wasteful number, since it uses less digits than its factorization.

221221221222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 899273303.

The product of its digits is 512, while the sum is 21.

Adding to 221221221222 its reverse (222122122122), we get a palindrome (443343343344).

It can be divided in two parts, 22122122122 and 2, that multiplied together give a palindrome (44244244244).

The spelling of 221221221222 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred twenty-two".