780816 has 20 divisors (see below), whose sum is σ = 2017232. Its totient is φ = 260256.

The previous prime is 780809. The next prime is 780817. The reversal of 780816 is 618087.

It is not an unprimeable number, because it can be changed into a prime (780817) by changing a digit.

780816 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8086 + ... + 8181.

2⁷⁸⁰⁸¹⁶ is an apocalyptic number.

It is an amenable number.

780816 is an abundant number, since it is smaller than the sum of its proper divisors (1236416).

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

780816 is a wasteful number, since it uses less digits than its factorization.

780816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16278 (or 16272 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 780816 is about 883.6379349032. The cubic root of 780816 is about 92.0837296972.

Subtracting from 780816 its product of nonzero digits (2688), we obtain a triangular number (778128 = T₁₂₄₇).

It can be divided in two parts, 78081 and 6, that added together give a palindrome (78087).

The spelling of 780816 in words is "seven hundred eighty thousand, eight hundred sixteen".