816787 has 4 divisors (see below), whose sum is σ = 824976. Its totient is φ = 808600.

The previous prime is 816779. The next prime is 816811. The reversal of 816787 is 787618.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 816787 - 2³ = 816779 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (816587) 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, 3943 + ... + 4144.

It is an arithmetic number, because the mean of its divisors is an integer number (206244).

2⁸¹⁶⁷⁸⁷ is an apocalyptic number.

816787 is a deficient number, since it is larger than the sum of its proper divisors (8189).

816787 is a wasteful number, since it uses less digits than its factorization.

816787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8188.

The product of its digits is 18816, while the sum is 37.

The square root of 816787 is about 903.7626900907. The cubic root of 816787 is about 93.4766067664.

The spelling of 816787 in words is "eight hundred sixteen thousand, seven hundred eighty-seven".