202001212121 has 4 divisors (see below), whose sum is σ = 202310556132. Its totient is φ = 201691868112.

The previous prime is 202001212051. The next prime is 202001212129. The reversal of 202001212121 is 121212100202.

202001212121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 123208722121 + 78792490000 = 351011^2 + 280700^2 .

It is a cyclic number.

It is not a de Polignac number, because 202001212121 - 2³⁰ = 200927470297 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 202001212096 and 202001212105.

It is not an unprimeable number, because it can be changed into a prime (202001212129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154671026 + ... + 154672331.

It is an arithmetic number, because the mean of its divisors is an integer number (50577639033).

Almost surely, 2^202001212121 is an apocalyptic number.

It is an amenable number.

202001212121 is a deficient number, since it is larger than the sum of its proper divisors (309344011).

202001212121 is an equidigital number, since it uses as much as digits as its factorization.

202001212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309344010.

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

Adding to 202001212121 its reverse (121212100202), we get a palindrome (323213312323).

It can be divided in two parts, 20200 and 1212121, that added together give a palindrome (1232321).

The spelling of 202001212121 in words is "two hundred two billion, one million, two hundred twelve thousand, one hundred twenty-one".