It is a congruent number.
It is an unprimeable number.
Almost surely, 2221323210100 is an apocalyptic number.
221323210100 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 221323210100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244092241680).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
221323210100 is a wasteful number, since it uses less digits than its factorization.
221323210100 is an evil number, because the sum of its binary digits is even.
Adding to 221323210100 its reverse (1012323122), we get a palindrome (222335533222).
The spelling of 221323210100 in words is "two hundred twenty-one billion, three hundred twenty-three million, two hundred ten thousand, one hundred".