765640 has 16 divisors (see below), whose sum is σ = 1722780. Its totient is φ = 306240.

The previous prime is 765623. The next prime is 765649. The reversal of 765640 is 46567.

It can be written as a sum of positive squares in 2 ways, for example, as 763876 + 1764 = 874^2 + 42^2 .

It is a junction number, because it is equal to n+sod(n) for n = 765599 and 765608.

It is not an unprimeable number, because it can be changed into a prime (765649) by changing a digit.

765640 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, 9531 + ... + 9610.

2⁷⁶⁵⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

765640 is an abundant number, since it is smaller than the sum of its proper divisors (957140).

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

765640 is a wasteful number, since it uses less digits than its factorization.

765640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19152 (or 19148 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 765640 is about 875.0085713866. The cubic root of 765640 is about 91.4832401843.

The spelling of 765640 in words is "seven hundred sixty-five thousand, six hundred forty".