12021221212 has 96 divisors (see below), whose sum is σ = 28902956544. Its totient is φ = 4222713600.

The previous prime is 12021221209. The next prime is 12021221231. The reversal of 12021221212 is 21212212021.

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 31 ways as a sum of consecutive naturals, for example, 137262 + ... + 207082.

It is an arithmetic number, because the mean of its divisors is an integer number (301072464).

Almost surely, 2^12021221212 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 12021221212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14451478272).

12021221212 is an abundant number, since it is smaller than the sum of its proper divisors (16881735332).

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

12021221212 is a wasteful number, since it uses less digits than its factorization.

12021221212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69899 (or 69897 counting only the distinct ones).

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

Adding to 12021221212 its reverse (21212212021), we get a palindrome (33233433233).

The spelling of 12021221212 in words is "twelve billion, twenty-one million, two hundred twenty-one thousand, two hundred twelve".