205815078 has 48 divisors (see below), whose sum is σ = 511538976. Its totient is φ = 58584960.

The previous prime is 205815061. The next prime is 205815079. The reversal of 205815078 is 870518502.

205815078 is a `hidden beast` number, since 2 + 0 + 581 + 5 + 0 + 78 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205815079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32500 + ... + 38312.

It is an arithmetic number, because the mean of its divisors is an integer number (10657062).

Almost surely, 2^205815078 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205815078, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (255769488).

205815078 is an abundant number, since it is smaller than the sum of its proper divisors (305723898).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

205815078 is a wasteful number, since it uses less digits than its factorization.

205815078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6109 (or 6106 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 36.

The square root of 205815078 is about 14346.2565849074. The cubic root of 205815078 is about 590.4172840413.

The spelling of 205815078 in words is "two hundred five million, eight hundred fifteen thousand, seventy-eight".