201221212101020 has 48 divisors (see below), whose sum is σ = 444964158105600. Its totient is φ = 76224927631680.

The previous prime is 201221212101017. The next prime is 201221212101029. The reversal of 201221212101020 is 20101212122102.

It is a self number, because there is not a number n which added to its sum of digits gives 201221212101020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201221212101029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 93803180 + ... + 95924339.

It is an arithmetic number, because the mean of its divisors is an integer number (9270086627200).

Almost surely, 2^{201221212101020} is an apocalyptic number.

201221212101020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201221212101020 is an abundant number, since it is smaller than the sum of its proper divisors (243742946004580).

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

201221212101020 is a wasteful number, since it uses less digits than its factorization.

201221212101020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189730338 (or 189730336 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 201221212101020 its reverse (20101212122102), we get a palindrome (221322424223122).

The spelling of 201221212101020 in words is "two hundred one trillion, two hundred twenty-one billion, two hundred twelve million, one hundred one thousand, twenty".