665331765 has 64 divisors (see below), whose sum is σ = 1282867200. Its totient is φ = 288011520.

The previous prime is 665331739. The next prime is 665331767. The reversal of 665331765 is 567133566.

It is a happy number.

It is not a de Polignac number, because 665331765 - 2¹⁰ = 665330741 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665331767) 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 63 ways as a sum of consecutive naturals, for example, 150811 + ... + 155159.

It is an arithmetic number, because the mean of its divisors is an integer number (20044800).

Almost surely, 2^665331765 is an apocalyptic number.

It is an amenable number.

665331765 is a deficient number, since it is larger than the sum of its proper divisors (617535435).

665331765 is a wasteful number, since it uses less digits than its factorization.

665331765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4442.

The product of its digits is 340200, while the sum is 42.

The square root of 665331765 is about 25794.0257617922. The cubic root of 665331765 is about 872.9970031217.

The spelling of 665331765 in words is "six hundred sixty-five million, three hundred thirty-one thousand, seven hundred sixty-five".