21220020110020 has 384 divisors, whose sum is σ = 50212866816000. Its totient is φ = 7495502192640.

The previous prime is 21220020110011. The next prime is 21220020110021. The reversal of 21220020110020 is 2001102002212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21220020110021) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 16436885575 + ... + 16436886865.

It is an arithmetic number, because the mean of its divisors is an integer number (130762674000).

Almost surely, 2^{21220020110020} is an apocalyptic number.

21220020110020 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 21220020110020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25106433408000).

21220020110020 is an abundant number, since it is smaller than the sum of its proper divisors (28992846705980).

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

21220020110020 is a wasteful number, since it uses less digits than its factorization.

21220020110020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1731 (or 1729 counting only the distinct ones).

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

Adding to 21220020110020 its reverse (2001102002212), we get a palindrome (23221122112232).

The spelling of 21220020110020 in words is "twenty-one trillion, two hundred twenty billion, twenty million, one hundred ten thousand, twenty".