221221010000 has 200 divisors, whose sum is σ = 551322820224. Its totient is φ = 85920640000.

The previous prime is 221221009991. The next prime is 221221010011. The reversal of 221221010000 is 10122122.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (200).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 61568204 + ... + 61571796.

Almost surely, 2^221221010000 is an apocalyptic number.

221221010000 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 221221010000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (275661410112).

221221010000 is an abundant number, since it is smaller than the sum of its proper divisors (330101810224).

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

221221010000 is a wasteful number, since it uses less digits than its factorization.

221221010000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3799 (or 3778 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 221221010000 its reverse (10122122), we get a palindrome (221231132122).

The spelling of 221221010000 in words is "two hundred twenty-one billion, two hundred twenty-one million, ten thousand".