202012121021 has 2 divisors, whose sum is σ = 202012121022. Its totient is φ = 202012121020.

The previous prime is 202012120991. The next prime is 202012121063. The reversal of 202012121021 is 120121210202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 199054284025 + 2957836996 = 446155^2 + 54386^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202012121021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 202012120987 and 202012121005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202012121071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101006060510 + 101006060511.

It is an arithmetic number, because the mean of its divisors is an integer number (101006060511).

Almost surely, 2^202012121021 is an apocalyptic number.

It is an amenable number.

202012121021 is a deficient number, since it is larger than the sum of its proper divisors (1).

202012121021 is an equidigital number, since it uses as much as digits as its factorization.

202012121021 is an evil number, because the sum of its binary digits is even.

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

Adding to 202012121021 its reverse (120121210202), we get a palindrome (322133331223).

The spelling of 202012121021 in words is "two hundred two billion, twelve million, one hundred twenty-one thousand, twenty-one".