21100221120 has 112 divisors (see below), whose sum is σ = 73083529728. Its totient is φ = 5115202560.

The previous prime is 21100221119. The next prime is 21100221209. The reversal of 21100221120 is 2112200112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21100221096 and 21100221105.

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 15 ways as a sum of consecutive naturals, for example, 988504 + ... + 1009623.

Almost surely, 2^21100221120 is an apocalyptic number.

21100221120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100221120 is an abundant number, since it is smaller than the sum of its proper divisors (51983308608).

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

21100221120 is a wasteful number, since it uses less digits than its factorization.

21100221120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1998158 (or 1998148 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21100221120 its reverse (2112200112), we get a palindrome (23212421232).

The spelling of 21100221120 in words is "twenty-one billion, one hundred million, two hundred twenty-one thousand, one hundred twenty".