82805 has 4 divisors (see below), whose sum is σ = 99372. Its totient is φ = 66240.

The previous prime is 82799. The next prime is 82811. The reversal of 82805 is 50828.

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

It is an interprime number because it is at equal distance from previous prime (82799) and next prime (82811).

It can be written as a sum of positive squares in 2 ways, for example, as 14161 + 68644 = 119^2 + 262^2 .

It is not a de Polignac number, because 82805 - 2⁸ = 82549 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 14.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8276 + ... + 8285.

It is an arithmetic number, because the mean of its divisors is an integer number (24843).

2⁸²⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

82805 is a deficient number, since it is larger than the sum of its proper divisors (16567).

82805 is a wasteful number, since it uses less digits than its factorization.

82805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16566.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 82805 is about 287.7585793682. The cubic root of 82805 is about 43.5865191327.

Adding to 82805 its sum of digits (23), we get a palindrome (82828).

The spelling of 82805 in words is "eighty-two thousand, eight hundred five".