205706560 has 28 divisors (see below), whose sum is σ = 489839508. Its totient is φ = 82282496.

The previous prime is 205706551. The next prime is 205706563. The reversal of 205706560 is 65607502.

It can be written as a sum of positive squares in 2 ways, for example, as 33362176 + 172344384 = 5776^2 + 13128^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205706563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321097 + ... + 321736.

Almost surely, 2^205706560 is an apocalyptic number.

205706560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205706560 is an abundant number, since it is smaller than the sum of its proper divisors (284132948).

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

205706560 is an equidigital number, since it uses as much as digits as its factorization.

205706560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 642850 (or 642840 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 31.

The square root of 205706560 is about 14342.4739846374. The cubic root of 205706560 is about 590.3134980482.

The spelling of 205706560 in words is "two hundred five million, seven hundred six thousand, five hundred sixty".