109805 has 4 divisors (see below), whose sum is σ = 131772. Its totient is φ = 87840.

The previous prime is 109793. The next prime is 109807. The reversal of 109805 is 508901.

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 64009 + 45796 = 253^2 + 214^2 .

It is not a de Polignac number, because 109805 - 2⁴ = 109789 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (109807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10976 + ... + 10985.

It is an arithmetic number, because the mean of its divisors is an integer number (32943).

2¹⁰⁹⁸⁰⁵ is an apocalyptic number.

It is an amenable number.

109805 is a deficient number, since it is larger than the sum of its proper divisors (21967).

109805 is an equidigital number, since it uses as much as digits as its factorization.

109805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21966.

The product of its (nonzero) digits is 360, while the sum is 23.

The square root of 109805 is about 331.3683750752. The cubic root of 109805 is about 47.8858688882.

The spelling of 109805 in words is "one hundred nine thousand, eight hundred five".