20210120011021 has 4 divisors (see below), whose sum is σ = 20210129794044. Its totient is φ = 20210110228000.

The previous prime is 20210120011019. The next prime is 20210120011061. The reversal of 20210120011021 is 12011002101202.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 10178875489225 + 10031244521796 = 3190435^2 + 3167214^2 .

It is a cyclic number.

It is not a de Polignac number, because 20210120011021 - 2¹ = 20210120011019 is a prime.

It is a super-2 number, since 2×20210120011021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20210120010992 and 20210120011010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20210120011061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 446080 + ... + 6373321.

It is an arithmetic number, because the mean of its divisors is an integer number (5052532448511).

Almost surely, 2^{20210120011021} is an apocalyptic number.

It is an amenable number.

20210120011021 is a deficient number, since it is larger than the sum of its proper divisors (9783023).

20210120011021 is an equidigital number, since it uses as much as digits as its factorization.

20210120011021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9783022.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20210120011021 its reverse (12011002101202), we get a palindrome (32221122112223).

The spelling of 20210120011021 in words is "twenty trillion, two hundred ten billion, one hundred twenty million, eleven thousand, twenty-one".