20201221021100 has 72 divisors (see below), whose sum is σ = 51264121886208. Its totient is φ = 6765060052800.

The previous prime is 20201221021073. The next prime is 20201221021139. The reversal of 20201221021100 is 112012210202.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 335538356 + ... + 335598555.

It is an arithmetic number, because the mean of its divisors is an integer number (712001692864).

Almost surely, 2^{20201221021100} is an apocalyptic number.

20201221021100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20201221021100 is an abundant number, since it is smaller than the sum of its proper divisors (31062900865108).

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

20201221021100 is a wasteful number, since it uses less digits than its factorization.

20201221021100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 671136975 (or 671136968 counting only the distinct ones).

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

Adding to 20201221021100 its reverse (112012210202), we get a palindrome (20313233231302).

The spelling of 20201221021100 in words is "twenty trillion, two hundred one billion, two hundred twenty-one million, twenty-one thousand, one hundred".