764820 has 72 divisors (see below), whose sum is σ = 2655744. Its totient is φ = 174528.

The previous prime is 764809. The next prime is 764837. The reversal of 764820 is 28467.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 764820.

It is an unprimeable 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 23 ways as a sum of consecutive naturals, for example, 957 + ... + 1563.

2⁷⁶⁴⁸²⁰ is an apocalyptic number.

764820 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 764820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1327872).

764820 is an abundant number, since it is smaller than the sum of its proper divisors (1890924).

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

764820 is a wasteful number, since it uses less digits than its factorization.

764820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 629 (or 624 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 764820 is about 874.5398790221. The cubic root of 764820 is about 91.4505690187.

The spelling of 764820 in words is "seven hundred sixty-four thousand, eight hundred twenty".