211021021220020 has 96 divisors (see below), whose sum is σ = 485468041766400. Its totient is φ = 76411434624000.

The previous prime is 211021021220003. The next prime is 211021021220089. The reversal of 211021021220020 is 20022120120112.

It is a happy number.

It is a super-2 number, since 2×211021021220020² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 211021021219976 and 211021021220003.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 3163652670 + ... + 3163719370.

It is an arithmetic number, because the mean of its divisors is an integer number (5056958768400).

Almost surely, 2^{211021021220020} is an apocalyptic number.

211021021220020 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 211021021220020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242734020883200).

211021021220020 is an abundant number, since it is smaller than the sum of its proper divisors (274447020546380).

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

211021021220020 is a wasteful number, since it uses less digits than its factorization.

211021021220020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127129 (or 127127 counting only the distinct ones).

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

Adding to 211021021220020 its reverse (20022120120112), we get a palindrome (231043141340132).

The spelling of 211021021220020 in words is "two hundred eleven trillion, twenty-one billion, twenty-one million, two hundred twenty thousand, twenty".