205001155 has 16 divisors (see below), whose sum is σ = 250725024. Its totient is φ = 160876800.

The previous prime is 205001123. The next prime is 205001179. The reversal of 205001155 is 551100502.

It is not a de Polignac number, because 205001155 - 2⁵ = 205001123 is a prime.

It is a Duffinian number.

205001155 is a modest number, since divided by 1155 gives 205 as remainder.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 70480 + ... + 73330.

It is an arithmetic number, because the mean of its divisors is an integer number (15670314).

Almost surely, 2^205001155 is an apocalyptic number.

205001155 is a deficient number, since it is larger than the sum of its proper divisors (45723869).

205001155 is a wasteful number, since it uses less digits than its factorization.

205001155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3126.

The product of its (nonzero) digits is 250, while the sum is 19.

The square root of 205001155 is about 14317.8613975691. The cubic root of 205001155 is about 589.6379613617.

Adding to 205001155 its reverse (551100502), we get a palindrome (756101657).

The spelling of 205001155 in words is "two hundred five million, one thousand, one hundred fifty-five".