221221120000 has 120 divisors (see below), whose sum is σ = 552744041850. Its totient is φ = 88487936000.

The previous prime is 221221119983. The next prime is 221221120069. The reversal of 221221120000 is 21122122.

It is a happy number.

It can be written as a sum of positive squares in 5 ways, for example, as 11266548736 + 209954571264 = 106144^2 + 458208^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1193586 + ... + 1366414.

Almost surely, 2^221221120000 is an apocalyptic number.

221221120000 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 221221120000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276372020925).

221221120000 is an abundant number, since it is smaller than the sum of its proper divisors (331522921850).

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

221221120000 is an frugal number, since it uses more digits than its factorization.

221221120000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172871 (or 172836 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 221221120000 its reverse (21122122), we get a palindrome (221242242122).

The spelling of 221221120000 in words is "two hundred twenty-one billion, two hundred twenty-one million, one hundred twenty thousand".