20211200100021 has 48 divisors (see below), whose sum is σ = 32036595552000. Its totient is φ = 11295890242560.

The previous prime is 20211200100017. The next prime is 20211200100059. The reversal of 20211200100021 is 12000100211202.

It is not a de Polignac number, because 20211200100021 - 2² = 20211200100017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211200100001) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9244605 + ... + 11219853.

It is an arithmetic number, because the mean of its divisors is an integer number (667429074000).

Almost surely, 2^{20211200100021} is an apocalyptic number.

20211200100021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20211200100021 is a deficient number, since it is larger than the sum of its proper divisors (11825395451979).

20211200100021 is a wasteful number, since it uses less digits than its factorization.

20211200100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1976794 (or 1976787 counting only the distinct ones).

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

Adding to 20211200100021 its reverse (12000100211202), we get a palindrome (32211300311223).

The spelling of 20211200100021 in words is "twenty trillion, two hundred eleven billion, two hundred million, one hundred thousand, twenty-one".