201221200021020 has 24 divisors (see below), whose sum is σ = 563419360059024. Its totient is φ = 53658986672256.

The previous prime is 201221200021007. The next prime is 201221200021111. The reversal of 201221200021020 is 20120002122102.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1676843333449 + ... + 1676843333568.

It is an arithmetic number, because the mean of its divisors is an integer number (23475806669126).

Almost surely, 2^{201221200021020} is an apocalyptic number.

201221200021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201221200021020 is an abundant number, since it is smaller than the sum of its proper divisors (362198160038004).

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

201221200021020 is a wasteful number, since it uses less digits than its factorization.

201221200021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3353686667029 (or 3353686667027 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 201221200021020 its reverse (20120002122102), we get a palindrome (221341202143122).

The spelling of 201221200021020 in words is "two hundred one trillion, two hundred twenty-one billion, two hundred million, twenty-one thousand, twenty".