816705 has 12 divisors (see below), whose sum is σ = 1415700. Its totient is φ = 435552.

The previous prime is 816703. The next prime is 816709. The reversal of 816705 is 507618.

It can be written as a sum of positive squares in 2 ways, for example, as 263169 + 553536 = 513^2 + 744^2 .

It is not a de Polignac number, because 816705 - 2¹ = 816703 is a prime.

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

It is a nialpdrome in base 16.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 816705.

It is not an unprimeable number, because it can be changed into a prime (816703) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9030 + ... + 9119.

It is an arithmetic number, because the mean of its divisors is an integer number (117975).

2⁸¹⁶⁷⁰⁵ is an apocalyptic number.

It is an amenable number.

816705 is a deficient number, since it is larger than the sum of its proper divisors (598995).

816705 is a wasteful number, since it uses less digits than its factorization.

816705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18160 (or 18157 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 816705 is about 903.7173230607. The cubic root of 816705 is about 93.4734785179.

It can be divided in two parts, 816 and 705, that added together give a square (1521 = 39²).

The spelling of 816705 in words is "eight hundred sixteen thousand, seven hundred five".