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BaseRepresentation
bin1111110101001
3102010012
41332221
5224410
6101305
732426
oct17651
912105
108105
1160a9
124835
1338c6
142d4d
152605
hex1fa9

8105 has 4 divisors (see below), whose sum is σ = 9732. Its totient is φ = 6480.

The previous prime is 8101. The next prime is 8111. The reversal of 8105 is 5018.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4624 + 3481 = 68^2 + 59^2 .

It is not a de Polignac number, because 8105 - 22 = 8101 is a prime.

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

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8105.

It is not an unprimeable number, because it can be changed into a prime (8101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 806 + ... + 815.

It is an arithmetic number, because the mean of its divisors is an integer number (2433).

28105 is an apocalyptic number.

It is an amenable number.

8105 is a deficient number, since it is larger than the sum of its proper divisors (1627).

8105 is a wasteful number, since it uses less digits than its factorization.

8105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1626.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 8105 is about 90.0277734924. The cubic root of 8105 is about 20.0871199546.

The spelling of 8105 in words is "eight thousand, one hundred five".

Divisors: 1 5 1621 8105