205604261 has 2 divisors, whose sum is σ = 205604262. Its totient is φ = 205604260.

The previous prime is 205604249. The next prime is 205604293. The reversal of 205604261 is 162406502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 115240225 + 90364036 = 10735^2 + 9506^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205604261 is a prime.

It is a super-2 number, since 2×205604261² = 84546224282712242, 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 205604261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205654261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102802130 + 102802131.

It is an arithmetic number, because the mean of its divisors is an integer number (102802131).

Almost surely, 2^205604261 is an apocalyptic number.

It is an amenable number.

205604261 is a deficient number, since it is larger than the sum of its proper divisors (1).

205604261 is an equidigital number, since it uses as much as digits as its factorization.

205604261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 205604261 is about 14338.9072456725. The cubic root of 205604261 is about 590.2156264428.

The spelling of 205604261 in words is "two hundred five million, six hundred four thousand, two hundred sixty-one".