204202421 has 2 divisors, whose sum is σ = 204202422. Its totient is φ = 204202420.

The previous prime is 204202409. The next prime is 204202469. The reversal of 204202421 is 124202402.

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., 188512900 + 15689521 = 13730^2 + 3961^2 .

It is a cyclic number.

It is not a de Polignac number, because 204202421 - 2¹⁸ = 203940277 is a prime.

It is a super-2 number, since 2×204202421² = 83397257484522482, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 204202421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204202321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102101210 + 102101211.

It is an arithmetic number, because the mean of its divisors is an integer number (102101211).

Almost surely, 2^204202421 is an apocalyptic number.

It is an amenable number.

204202421 is a deficient number, since it is larger than the sum of its proper divisors (1).

204202421 is an equidigital number, since it uses as much as digits as its factorization.

204202421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 17.

The square root of 204202421 is about 14289.9412525035. The cubic root of 204202421 is about 588.8711740106.

Adding to 204202421 its reverse (124202402), we get a palindrome (328404823).

The spelling of 204202421 in words is "two hundred four million, two hundred two thousand, four hundred twenty-one".