665264985 has 32 divisors (see below), whose sum is σ = 1327076352. Its totient is φ = 276473280.

The previous prime is 665264983. The next prime is 665265023. The reversal of 665264985 is 589462566.

It is not a de Polignac number, because 665264985 - 2¹ = 665264983 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (665264983) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 286839 + ... + 289148.

It is an arithmetic number, because the mean of its divisors is an integer number (41471136).

Almost surely, 2^665264985 is an apocalyptic number.

It is an amenable number.

665264985 is a deficient number, since it is larger than the sum of its proper divisors (661811367).

665264985 is a wasteful number, since it uses less digits than its factorization.

665264985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576013.

The product of its digits is 3110400, while the sum is 51.

The square root of 665264985 is about 25792.7312435112. The cubic root of 665264985 is about 872.9677942901.

The spelling of 665264985 in words is "six hundred sixty-five million, two hundred sixty-four thousand, nine hundred eighty-five".