221201121221200 has 120 divisors (see below), whose sum is σ = 559436728356000. Its totient is φ = 83818977338880.

The previous prime is 221201121221177. The next prime is 221201121221233. The reversal of 221201121221200 is 2122121102122.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 139148451 + ... + 140729149.

It is an arithmetic number, because the mean of its divisors is an integer number (4661972736300).

Almost surely, 2^{221201121221200} is an apocalyptic number.

221201121221200 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 221201121221200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (279718364178000).

221201121221200 is an abundant number, since it is smaller than the sum of its proper divisors (338235607134800).

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

221201121221200 is a wasteful number, since it uses less digits than its factorization.

221201121221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1599149 (or 1599138 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 221201121221200 its reverse (2122121102122), we get a palindrome (223323242323322).

The spelling of 221201121221200 in words is "two hundred twenty-one trillion, two hundred one billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred".