202020210021121 has 4 divisors (see below), whose sum is σ = 202020653650500. Its totient is φ = 202019766391744.

The previous prime is 202020210021023. The next prime is 202020210021127. The reversal of 202020210021121 is 121120012020202.

It is a happy number.

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 78885678461121 + 123134531560000 = 8881761^2 + 11096600^2 .

It is a cyclic number.

It is not a de Polignac number, because 202020210021121 - 2¹¹ = 202020210019073 is a prime.

It is a super-2 number, since 2×202020210021121² (a number of 29 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 = 202020210021095 and 202020210021104.

It is not an unprimeable number, because it can be changed into a prime (202020210021127) 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, 221130916 + ... + 222042613.

It is an arithmetic number, because the mean of its divisors is an integer number (50505163412625).

Almost surely, 2^{202020210021121} is an apocalyptic number.

It is an amenable number.

202020210021121 is a deficient number, since it is larger than the sum of its proper divisors (443629379).

202020210021121 is an equidigital number, since it uses as much as digits as its factorization.

202020210021121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443629378.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 202020210021121 its reverse (121120012020202), we get a palindrome (323140222041323).

The spelling of 202020210021121 in words is "two hundred two trillion, twenty billion, two hundred ten million, twenty-one thousand, one hundred twenty-one".