20210101202021 has 4 divisors (see below), whose sum is σ = 20907001243500. Its totient is φ = 19513201160544.

The previous prime is 20210101202009. The next prime is 20210101202047. The reversal of 20210101202021 is 12020210101202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7477550409121 + 12732550792900 = 2734511^2 + 3568270^2 .

It is not a de Polignac number, because 20210101202021 - 2³⁸ = 19935223295077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20210101201987 and 20210101202005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20210101208021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 348450020696 + ... + 348450020753.

It is an arithmetic number, because the mean of its divisors is an integer number (5226750310875).

Almost surely, 2^{20210101202021} is an apocalyptic number.

It is an amenable number.

20210101202021 is a deficient number, since it is larger than the sum of its proper divisors (696900041479).

20210101202021 is an equidigital number, since it uses as much as digits as its factorization.

20210101202021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696900041478.

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

Adding to 20210101202021 its reverse (12020210101202), we get a palindrome (32230311303223).

The spelling of 20210101202021 in words is "twenty trillion, two hundred ten billion, one hundred one million, two hundred two thousand, twenty-one".