201211220100020 has 96 divisors (see below), whose sum is σ = 459573072809760. Its totient is φ = 73554475161600.

The previous prime is 201211220100001. The next prime is 201211220100053. The reversal of 201211220100020 is 20001022112102.

It can be written as a sum of positive squares in 16 ways, for example, as 83813951760016 + 117397268340004 = 9154996^2 + 10835002^2 .

It is a junction number, because it is equal to n+sod(n) for n = 201211220099968 and 201211220100004.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 624538094 + ... + 624860186.

It is an arithmetic number, because the mean of its divisors is an integer number (4787219508435).

Almost surely, 2^{201211220100020} is an apocalyptic number.

201211220100020 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 201211220100020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229786536404880).

201211220100020 is an abundant number, since it is smaller than the sum of its proper divisors (258361852709740).

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

201211220100020 is a wasteful number, since it uses less digits than its factorization.

201211220100020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346005 (or 346003 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 201211220100020 its reverse (20001022112102), we get a palindrome (221212242212122).

The spelling of 201211220100020 in words is "two hundred one trillion, two hundred eleven billion, two hundred twenty million, one hundred thousand, twenty".