204509957 has 2 divisors, whose sum is σ = 204509958. Its totient is φ = 204509956.

The previous prime is 204509953. The next prime is 204509971. The reversal of 204509957 is 759905402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 200533921 + 3976036 = 14161^2 + 1994^2 .

It is a cyclic number.

It is not a de Polignac number, because 204509957 - 2² = 204509953 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204509953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102254978 + 102254979.

It is an arithmetic number, because the mean of its divisors is an integer number (102254979).

Almost surely, 2^204509957 is an apocalyptic number.

It is an amenable number.

204509957 is a deficient number, since it is larger than the sum of its proper divisors (1).

204509957 is an equidigital number, since it uses as much as digits as its factorization.

204509957 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 113400, while the sum is 41.

The square root of 204509957 is about 14300.6977801784. The cubic root of 204509957 is about 589.1666459360.

The spelling of 204509957 in words is "two hundred four million, five hundred nine thousand, nine hundred fifty-seven".