809816 has 16 divisors (see below), whose sum is σ = 1735440. Its totient is φ = 347040.

The previous prime is 809803. The next prime is 809821. The reversal of 809816 is 618908.

809816 = T₁₇₅ + T₁₇₆ + ... + T₂₁₆.

809816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

809816 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, 7175 + ... + 7286.

It is an arithmetic number, because the mean of its divisors is an integer number (108465).

2⁸⁰⁹⁸¹⁶ is an apocalyptic number.

It is an amenable number.

809816 is an abundant number, since it is smaller than the sum of its proper divisors (925624).

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

809816 is a wasteful number, since it uses less digits than its factorization.

809816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14474 (or 14470 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 809816 is about 899.8977719719. The cubic root of 809816 is about 93.2099162394.

The spelling of 809816 in words is "eight hundred nine thousand, eight hundred sixteen".