205171145 has 4 divisors (see below), whose sum is σ = 246205380. Its totient is φ = 164136912.

The previous prime is 205171117. The next prime is 205171157. The reversal of 205171145 is 541171502.

205171145 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 88811776 + 116359369 = 9424^2 + 10787^2 .

It is a cyclic number.

It is not a de Polignac number, because 205171145 - 2⁶ = 205171081 is a prime.

It is a super-2 number, since 2×205171145² = 84190397481222050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20517110 + ... + 20517119.

It is an arithmetic number, because the mean of its divisors is an integer number (61551345).

Almost surely, 2^205171145 is an apocalyptic number.

It is an amenable number.

205171145 is a deficient number, since it is larger than the sum of its proper divisors (41034235).

205171145 is an equidigital number, since it uses as much as digits as its factorization.

205171145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41034234.

The product of its (nonzero) digits is 1400, while the sum is 26.

The square root of 205171145 is about 14323.7964590398. The cubic root of 205171145 is about 589.8008951836.

The spelling of 205171145 in words is "two hundred five million, one hundred seventy-one thousand, one hundred forty-five".