665550585 has 72 divisors (see below), whose sum is σ = 1346871240. Its totient is φ = 303141888.

The previous prime is 665550583. The next prime is 665550617. The reversal of 665550585 is 585055566.

665550585 is a `hidden beast` number, since 6 + 65 + 5 + 5 + 0 + 585 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 181198521 + 484352064 = 13461^2 + 22008^2 .

It is not a de Polignac number, because 665550585 - 2¹ = 665550583 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 665550585.

It is not an unprimeable number, because it can be changed into a prime (665550583) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1122049 + ... + 1122641.

It is an arithmetic number, because the mean of its divisors is an integer number (18706545).

Almost surely, 2^665550585 is an apocalyptic number.

It is an amenable number.

665550585 is an abundant number, since it is smaller than the sum of its proper divisors (681320655).

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

665550585 is a wasteful number, since it uses less digits than its factorization.

665550585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1127 (or 1117 counting only the distinct ones).

The product of its (nonzero) digits is 900000, while the sum is 45.

The square root of 665550585 is about 25798.2670929658. The cubic root of 665550585 is about 873.0926988712.

The spelling of 665550585 in words is "six hundred sixty-five million, five hundred fifty thousand, five hundred eighty-five".