211001121221020 has 192 divisors, whose sum is σ = 508214118295296. Its totient is φ = 72896631275520.

The previous prime is 211001121220979. The next prime is 211001121221041. The reversal of 211001121221020 is 20122121100112.

It is a junction number, because it is equal to n+sod(n) for n = 211001121220985 and 211001121221003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1288891812 + ... + 1289055508.

It is an arithmetic number, because the mean of its divisors is an integer number (2646948532788).

Almost surely, 2^{211001121221020} is an apocalyptic number.

211001121221020 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 211001121221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (254107059147648).

211001121221020 is an abundant number, since it is smaller than the sum of its proper divisors (297212997074276).

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

211001121221020 is a wasteful number, since it uses less digits than its factorization.

211001121221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165440 (or 165438 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 211001121221020 its reverse (20122121100112), we get a palindrome (231123242321132).

The spelling of 211001121221020 in words is "two hundred eleven trillion, one billion, one hundred twenty-one million, two hundred twenty-one thousand, twenty".