202105021 has 2 divisors, whose sum is σ = 202105022. Its totient is φ = 202105020.

The previous prime is 202105019. The next prime is 202105037. The reversal of 202105021 is 120501202.

202105021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 130279396 + 71825625 = 11414^2 + 8475^2 .

It is a cyclic number.

It is not a de Polignac number, because 202105021 - 2¹ = 202105019 is a prime.

Together with 202105019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 202104992 and 202105010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202105081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101052510 + 101052511.

It is an arithmetic number, because the mean of its divisors is an integer number (101052511).

Almost surely, 2^202105021 is an apocalyptic number.

It is an amenable number.

202105021 is a deficient number, since it is larger than the sum of its proper divisors (1).

202105021 is an equidigital number, since it uses as much as digits as its factorization.

202105021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 202105021 is about 14216.3645493495. The cubic root of 202105021 is about 586.8480975456.

Adding to 202105021 its reverse (120501202), we get a palindrome (322606223).

The spelling of 202105021 in words is "two hundred two million, one hundred five thousand, twenty-one".