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8705 = 51741
BaseRepresentation
bin10001000000001
3102221102
42020001
5234310
6104145
734244
oct21001
912842
108705
1165a4
125055
133c68
14325b
1528a5
hex2201

8705 has 4 divisors (see below), whose sum is σ = 10452. Its totient is φ = 6960.

The previous prime is 8699. The next prime is 8707. The reversal of 8705 is 5078.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5078 = 22539.

It can be written as a sum of positive squares in 2 ways, for example, as 961 + 7744 = 31^2 + 88^2 .

It is not a de Polignac number, because 8705 - 24 = 8689 is a prime.

It is an Ulam number.

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

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 8705.

It is not an unprimeable number, because it can be changed into a prime (8707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 866 + ... + 875.

It is an arithmetic number, because the mean of its divisors is an integer number (2613).

It is a Proth number, since it is equal to 17 ⋅ 29 + 1 and 17 < 29.

28705 is an apocalyptic number.

It is an amenable number.

8705 is a deficient number, since it is larger than the sum of its proper divisors (1747).

8705 is a wasteful number, since it uses less digits than its factorization.

8705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1746.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 8705 is about 93.3005894944. The cubic root of 8705 is about 20.5710404652.

The spelling of 8705 in words is "eight thousand, seven hundred five".

Divisors: 1 5 1741 8705