205381109 has 4 divisors (see below), whose sum is σ = 206611104. Its totient is φ = 204151116.

The previous prime is 205381087. The next prime is 205381123. The reversal of 205381109 is 901183502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205381109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205381409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 614747 + ... + 615080.

It is an arithmetic number, because the mean of its divisors is an integer number (51652776).

Almost surely, 2^205381109 is an apocalyptic number.

It is an amenable number.

205381109 is a deficient number, since it is larger than the sum of its proper divisors (1229995).

205381109 is a wasteful number, since it uses less digits than its factorization.

205381109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1229994.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 205381109 is about 14331.1237870587. The cubic root of 205381109 is about 590.0020195277.

The spelling of 205381109 in words is "two hundred five million, three hundred eighty-one thousand, one hundred nine".