10202020121 has 2 divisors, whose sum is σ = 10202020122. Its totient is φ = 10202020120.

The previous prime is 10202020099. The next prime is 10202020163. The reversal of 10202020121 is 12102020201.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8171256025 + 2030764096 = 90395^2 + 45064^2 .

It is a cyclic number.

It is not a de Polignac number, because 10202020121 - 2²⁶ = 10134911257 is a prime.

It is not a weakly prime, because it can be changed into another prime (10202022121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5101010060 + 5101010061.

It is an arithmetic number, because the mean of its divisors is an integer number (5101010061).

Almost surely, 2^10202020121 is an apocalyptic number.

It is an amenable number.

10202020121 is a deficient number, since it is larger than the sum of its proper divisors (1).

10202020121 is an equidigital number, since it uses as much as digits as its factorization.

10202020121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 10202020121 its reverse (12102020201), we get a palindrome (22304040322).

The spelling of 10202020121 in words is "ten billion, two hundred two million, twenty thousand, one hundred twenty-one".