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10805 = 52161
BaseRepresentation
bin10101000110101
3112211012
42220311
5321210
6122005
743334
oct25065
915735
1010805
118133
126305
134bc2
143d1b
153305
hex2a35

10805 has 4 divisors (see below), whose sum is σ = 12972. Its totient is φ = 8640.

The previous prime is 10799. The next prime is 10831. The reversal of 10805 is 50801.

10805 = 732 + 742.

10805 is nontrivially palindromic in base 7.

10805 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

10805 is an esthetic number in base 5, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50801 = 371373.

It can be written as a sum of positive squares in 2 ways, for example, as 5329 + 5476 = 73^2 + 74^2 .

It is not a de Polignac number, because 10805 - 24 = 10789 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 10805.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1076 + ... + 1085.

It is an arithmetic number, because the mean of its divisors is an integer number (3243).

210805 is an apocalyptic number.

10805 is the 74-th centered square number.

It is an amenable number.

10805 is a deficient number, since it is larger than the sum of its proper divisors (2167).

10805 is an equidigital number, since it uses as much as digits as its factorization.

10805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2166.

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

The square root of 10805 is about 103.9471019317. The cubic root of 10805 is about 22.1075996058.

The spelling of 10805 in words is "ten thousand, eight hundred five".

Divisors: 1 5 2161 10805