20100120200021 has 16 divisors (see below), whose sum is σ = 21276518880000. Its totient is φ = 18935796067776.

The previous prime is 20100120200003. The next prime is 20100120200033. The reversal of 20100120200021 is 12000202100102.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20100120200021 - 2³⁴ = 20082940330837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20100120199975 and 20100120200011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100120200071) 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, 98015 + ... + 6341123.

It is an arithmetic number, because the mean of its divisors is an integer number (1329782430000).

Almost surely, 2^{20100120200021} is an apocalyptic number.

It is an amenable number.

20100120200021 is a deficient number, since it is larger than the sum of its proper divisors (1176398679979).

20100120200021 is a wasteful number, since it uses less digits than its factorization.

20100120200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6244076.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 20100120200021 its reverse (12000202100102), we get a palindrome (32100322300123).

The spelling of 20100120200021 in words is "twenty trillion, one hundred billion, one hundred twenty million, two hundred thousand, twenty-one".