204122021 has 2 divisors, whose sum is σ = 204122022. Its totient is φ = 204122020.

The previous prime is 204121979. The next prime is 204122057. The reversal of 204122021 is 120221402.

204122021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165508225 + 38613796 = 12865^2 + 6214^2 .

It is a cyclic number.

It is not a de Polignac number, because 204122021 - 2¹⁰ = 204120997 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 204121987 and 204122005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204122221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102061010 + 102061011.

It is an arithmetic number, because the mean of its divisors is an integer number (102061011).

Almost surely, 2^204122021 is an apocalyptic number.

It is an amenable number.

204122021 is a deficient number, since it is larger than the sum of its proper divisors (1).

204122021 is an equidigital number, since it uses as much as digits as its factorization.

204122021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 204122021 is about 14287.1278079256. The cubic root of 204122021 is about 588.7938790448.

Adding to 204122021 its reverse (120221402), we get a palindrome (324343423).

The spelling of 204122021 in words is "two hundred four million, one hundred twenty-two thousand, twenty-one".