764840 has 16 divisors (see below), whose sum is σ = 1720980. Its totient is φ = 305920.

The previous prime is 764839. The next prime is 764849. The reversal of 764840 is 48467.

It can be written as a sum of positive squares in 2 ways, for example, as 749956 + 14884 = 866^2 + 122^2 .

It is not an unprimeable number, because it can be changed into a prime (764849) by changing a digit.

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, 9521 + ... + 9600.

2⁷⁶⁴⁸⁴⁰ is an apocalyptic number.

It is an amenable number.

764840 is an abundant number, since it is smaller than the sum of its proper divisors (956140).

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

764840 is a wasteful number, since it uses less digits than its factorization.

764840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19132 (or 19128 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 764840 is about 874.5513135317. The cubic root of 764840 is about 91.4513661542.

The spelling of 764840 in words is "seven hundred sixty-four thousand, eight hundred forty".