21220110021100 has 144 divisors (see below), whose sum is σ = 47782284793600. Its totient is φ = 8171228160000.

The previous prime is 21220110021079. The next prime is 21220110021107. The reversal of 21220110021100 is 112001102212.

It is not an unprimeable number, because it can be changed into a prime (21220110021107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 852577456 + ... + 852602344.

Almost surely, 2^{21220110021100} is an apocalyptic number.

21220110021100 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 21220110021100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23891142396800).

21220110021100 is an abundant number, since it is smaller than the sum of its proper divisors (26562174772500).

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

21220110021100 is a wasteful number, since it uses less digits than its factorization.

21220110021100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26364 (or 26357 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21220110021100 its reverse (112001102212), we get a palindrome (21332111123312).

The spelling of 21220110021100 in words is "twenty-one trillion, two hundred twenty billion, one hundred ten million, twenty-one thousand, one hundred".