204243121 has 2 divisors, whose sum is σ = 204243122. Its totient is φ = 204243120.

The previous prime is 204243113. The next prime is 204243131. The reversal of 204243121 is 121342402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 204175521 + 67600 = 14289^2 + 260^2 .

It is a cyclic number.

It is not a de Polignac number, because 204243121 - 2³ = 204243113 is a prime.

It is not a weakly prime, because it can be changed into another prime (204243101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102121560 + 102121561.

It is an arithmetic number, because the mean of its divisors is an integer number (102121561).

Almost surely, 2^204243121 is an apocalyptic number.

It is an amenable number.

204243121 is a deficient number, since it is larger than the sum of its proper divisors (1).

204243121 is an equidigital number, since it uses as much as digits as its factorization.

204243121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 204243121 is about 14291.3652601842. The cubic root of 204243121 is about 588.9102944489.

Adding to 204243121 its reverse (121342402), we get a palindrome (325585523).

The spelling of 204243121 in words is "two hundred four million, two hundred forty-three thousand, one hundred twenty-one".