765664 has 24 divisors (see below), whose sum is σ = 1533168. Its totient is φ = 376320.

The previous prime is 765659. The next prime is 765673. The reversal of 765664 is 466567.

It is a congruent number.

It is an unprimeable number.

765664 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2104 + ... + 2440.

It is an arithmetic number, because the mean of its divisors is an integer number (63882).

2⁷⁶⁵⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

765664 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

765664 is a wasteful number, since it uses less digits than its factorization.

765664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 410 counting only the distinct ones).

The product of its digits is 30240, while the sum is 34.

The square root of 765664 is about 875.0222854305. The cubic root of 765664 is about 91.4841960621.

It can be divided in two parts, 7656 and 64, that multiplied together give a palindrome (489984).

The spelling of 765664 in words is "seven hundred sixty-five thousand, six hundred sixty-four".