21202102112020 has 96 divisors (see below), whose sum is σ = 47377665054720. Its totient is φ = 7956094218240.

The previous prime is 21202102111979. The next prime is 21202102112041. The reversal of 21202102112020 is 2021120120212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21202102111985 and 21202102112003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2538084 + ... + 6988996.

It is an arithmetic number, because the mean of its divisors is an integer number (493517344320).

Almost surely, 2^{21202102112020} is an apocalyptic number.

21202102112020 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 21202102112020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23688832527360).

21202102112020 is an abundant number, since it is smaller than the sum of its proper divisors (26175562942700).

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

21202102112020 is a wasteful number, since it uses less digits than its factorization.

21202102112020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4451185 (or 4451183 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21202102112020 its reverse (2021120120212), we get a palindrome (23223222232232).

The spelling of 21202102112020 in words is "twenty-one trillion, two hundred two billion, one hundred two million, one hundred twelve thousand, twenty".