221421203572212 has 144 divisors (see below), whose sum is σ = 643137035433984. Its totient is φ = 62919573120000.

The previous prime is 221421203572187. The next prime is 221421203572249. The reversal of 221421203572212 is 212275302124122.

It is a happy number.

221421203572212 is a `hidden beast` number, since 2 + 2 + 1 + 42 + 1 + 20 + 3 + 572 + 21 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 245070412 + ... + 245972252.

It is an arithmetic number, because the mean of its divisors is an integer number (4466229412736).

Almost surely, 2^{221421203572212} 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 221421203572212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (321568517716992).

221421203572212 is an abundant number, since it is smaller than the sum of its proper divisors (421715831861772).

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

221421203572212 is a wasteful number, since it uses less digits than its factorization.

221421203572212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 907150 (or 907145 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

Adding to 221421203572212 its reverse (212275302124122), we get a palindrome (433696505696334).

The spelling of 221421203572212 in words is "two hundred twenty-one trillion, four hundred twenty-one billion, two hundred three million, five hundred seventy-two thousand, two hundred twelve".