Adding to 21380441600 its reverse (614408312), we get a palindrome (21994849912).
It is a congruent number.
It is an unprimeable number.
Almost surely, 221380441600 is an apocalyptic number.
21380441600 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 21380441600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31994865144).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
21380441600 is an equidigital number, since it uses as much as digits as its factorization.
21380441600 is an odious number, because the sum of its binary digits is odd.
The spelling of 21380441600 in words is "twenty-one billion, three hundred eighty million, four hundred forty-one thousand, six hundred".