816831 has 8 divisors (see below), whose sum is σ = 1210160. Its totient is φ = 544536.

The previous prime is 816821. The next prime is 816839. The reversal of 816831 is 138618.

It is not a de Polignac number, because 816831 - 2⁷ = 816703 is a prime.

It is a super-2 number, since 2×816831² = 1334425765122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 30253 = 816831 / (8 + 1 + 6 + 8 + 3 + 1).

It is a Duffinian number.

816831 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 816795 and 816804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816839) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15100 + ... + 15153.

It is an arithmetic number, because the mean of its divisors is an integer number (151270).

2⁸¹⁶⁸³¹ is an apocalyptic number.

816831 is a deficient number, since it is larger than the sum of its proper divisors (393329).

816831 is a wasteful number, since it uses less digits than its factorization.

816831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30262 (or 30256 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 816831 is about 903.7870324363. The cubic root of 816831 is about 93.4782852525.

The spelling of 816831 in words is "eight hundred sixteen thousand, eight hundred thirty-one".