205254409 has 2 divisors, whose sum is σ = 205254410. Its totient is φ = 205254408.

The previous prime is 205254391. The next prime is 205254419. The reversal of 205254409 is 904452502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 145733184 + 59521225 = 12072^2 + 7715^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205254409 is a prime.

It is not a weakly prime, because it can be changed into another prime (205254419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102627204 + 102627205.

It is an arithmetic number, because the mean of its divisors is an integer number (102627205).

Almost surely, 2^205254409 is an apocalyptic number.

It is an amenable number.

205254409 is a deficient number, since it is larger than the sum of its proper divisors (1).

205254409 is an equidigital number, since it uses as much as digits as its factorization.

205254409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 205254409 is about 14326.7026562290. The cubic root of 205254409 is about 589.8806701116.

The spelling of 205254409 in words is "two hundred five million, two hundred fifty-four thousand, four hundred nine".