205217055 has 48 divisors (see below), whose sum is σ = 369917184. Its totient is φ = 105131520.

The previous prime is 205217053. The next prime is 205217057. The reversal of 205217055 is 550712502.

It is a happy number.

205217055 is a `hidden beast` number, since 20 + 521 + 70 + 55 = 666.

It is an interprime number because it is at equal distance from previous prime (205217053) and next prime (205217057).

It is not a de Polignac number, because 205217055 - 2¹ = 205217053 is a prime.

It is a super-2 number, since 2×205217055² = 84228079325746050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205217053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 218547 + ... + 219483.

It is an arithmetic number, because the mean of its divisors is an integer number (7706608).

Almost surely, 2^205217055 is an apocalyptic number.

205217055 is a deficient number, since it is larger than the sum of its proper divisors (164700129).

205217055 is a wasteful number, since it uses less digits than its factorization.

205217055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1136 (or 1133 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The square root of 205217055 is about 14325.3989473243. The cubic root of 205217055 is about 589.8448840523.

Adding to 205217055 its reverse (550712502), we get a palindrome (755929557).

The spelling of 205217055 in words is "two hundred five million, two hundred seventeen thousand, fifty-five".