816940 has 12 divisors (see below), whose sum is σ = 1715616. Its totient is φ = 326768.

The previous prime is 816929. The next prime is 816941. The reversal of 816940 is 49618.

It is a junction number, because it is equal to n+sod(n) for n = 816899 and 816908.

It is not an unprimeable number, because it can be changed into a prime (816941) 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, 20404 + ... + 20443.

It is an arithmetic number, because the mean of its divisors is an integer number (142968).

2⁸¹⁶⁹⁴⁰ is an apocalyptic number.

It is an amenable number.

816940 is an abundant number, since it is smaller than the sum of its proper divisors (898676).

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

816940 is a wasteful number, since it uses less digits than its factorization.

816940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40856 (or 40854 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 816940 is about 903.8473322415. The cubic root of 816940 is about 93.4824430607.

It can be divided in two parts, 81 and 6940, that added together give a triangular number (7021 = T₁₁₈).

The spelling of 816940 in words is "eight hundred sixteen thousand, nine hundred forty".