204109121 has 2 divisors, whose sum is σ = 204109122. Its totient is φ = 204109120.

The previous prime is 204109117. The next prime is 204109141. The reversal of 204109121 is 121901402.

It is an a-pointer prime, because the next prime (204109141) can be obtained adding 204109121 to its sum of digits (20).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110019121 + 94090000 = 10489^2 + 9700^2 .

It is a cyclic number.

It is not a de Polignac number, because 204109121 - 2² = 204109117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 204109093 and 204109102.

It is not a weakly prime, because it can be changed into another prime (204109141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102054560 + 102054561.

It is an arithmetic number, because the mean of its divisors is an integer number (102054561).

Almost surely, 2^204109121 is an apocalyptic number.

It is an amenable number.

204109121 is a deficient number, since it is larger than the sum of its proper divisors (1).

204109121 is an equidigital number, since it uses as much as digits as its factorization.

204109121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 204109121 is about 14286.6763454626. The cubic root of 204109121 is about 588.7814753511.

The spelling of 204109121 in words is "two hundred four million, one hundred nine thousand, one hundred twenty-one".