221121212220012 has 96 divisors (see below), whose sum is σ = 563709979058688. Its totient is φ = 67050404688384.

The previous prime is 221121212220011. The next prime is 221121212220019. The reversal of 221121212220012 is 210022212121122.

It is not an unprimeable number, because it can be changed into a prime (221121212220011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5989243 + ... + 21865805.

It is an arithmetic number, because the mean of its divisors is an integer number (5871978948528).

Almost surely, 2^{221121212220012} 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 221121212220012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (281854989529344).

221121212220012 is an abundant number, since it is smaller than the sum of its proper divisors (342588766838676).

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

221121212220012 is a wasteful number, since it uses less digits than its factorization.

221121212220012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15877879 (or 15877877 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 221121212220012 its reverse (210022212121122), we get a palindrome (431143424341134).

The spelling of 221121212220012 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, two hundred twelve million, two hundred twenty thousand, twelve".