109840 has 20 divisors (see below), whose sum is σ = 255564. Its totient is φ = 43904.

The previous prime is 109831. The next prime is 109841. The reversal of 109840 is 48901.

It can be written as a sum of positive squares in 2 ways, for example, as 82944 + 26896 = 288^2 + 164^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (109841) by changing a digit.

109840 is an untouchable number, because it is not equal to the sum of proper divisors of any 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, 607 + ... + 766.

2¹⁰⁹⁸⁴⁰ is an apocalyptic number.

109840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

109840 is an abundant number, since it is smaller than the sum of its proper divisors (145724).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

109840 is a wasteful number, since it uses less digits than its factorization.

109840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1386 (or 1380 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 109840 is about 331.4211821836. The cubic root of 109840 is about 47.8909561714.

It can be divided in two parts, 109 and 840, that added together give a palindrome (949).

The spelling of 109840 in words is "one hundred nine thousand, eight hundred forty".