221212322212 has 72 divisors (see below), whose sum is σ = 456123648960. Its totient is φ = 93863733600.

The previous prime is 221212322209. The next prime is 221212322237. The reversal of 221212322212 is 212223212122.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6773739 + ... + 6806317.

It is an arithmetic number, because the mean of its divisors is an integer number (6335050680).

Almost surely, 2^221212322212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221212322212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (228061824480).

221212322212 is an abundant number, since it is smaller than the sum of its proper divisors (234911326748).

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

221212322212 is an equidigital number, since it uses as much as digits as its factorization.

221212322212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32719 (or 32689 counting only the distinct ones).

The product of its digits is 768, while the sum is 22.

Adding to 221212322212 its reverse (212223212122), we get a palindrome (433435534334).

The spelling of 221212322212 in words is "two hundred twenty-one billion, two hundred twelve million, three hundred twenty-two thousand, two hundred twelve".