221212000002120 has 256 divisors, whose sum is σ = 722894141410560. Its totient is φ = 53927300431872.

The previous prime is 221212000002107. The next prime is 221212000002121. The reversal of 221212000002120 is 21200000212122.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 221212000002120.

It is not an unprimeable number, because it can be changed into a prime (221212000002121) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 41810392 + ... + 46803128.

It is an arithmetic number, because the mean of its divisors is an integer number (2823805239885).

Almost surely, 2^{221212000002120} is an apocalyptic number.

221212000002120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221212000002120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (361447070705280).

221212000002120 is an abundant number, since it is smaller than the sum of its proper divisors (501682141408440).

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

221212000002120 is a wasteful number, since it uses less digits than its factorization.

221212000002120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4993392 (or 4993388 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 221212000002120 its reverse (21200000212122), we get a palindrome (242412000214242).

The spelling of 221212000002120 in words is "two hundred twenty-one trillion, two hundred twelve billion, two thousand, one hundred twenty".