211001221020 has 96 divisors (see below), whose sum is σ = 606727554048. Its totient is φ = 54759866112.

The previous prime is 211001221019. The next prime is 211001221033. The reversal of 211001221020 is 20122100112.

211001221020 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 211001220987 and 211001221005.

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, 567037 + ... + 862283.

It is an arithmetic number, because the mean of its divisors is an integer number (6320078688).

Almost surely, 2^211001221020 is an apocalyptic number.

211001221020 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 211001221020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303363777024).

211001221020 is an abundant number, since it is smaller than the sum of its proper divisors (395726333028).

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

211001221020 is a wasteful number, since it uses less digits than its factorization.

211001221020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295579 (or 295577 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 211001221020 its reverse (20122100112), we get a palindrome (231123321132).

The spelling of 211001221020 in words is "two hundred eleven billion, one million, two hundred twenty-one thousand, twenty".