109645 has 4 divisors (see below), whose sum is σ = 131580. Its totient is φ = 87712.

The previous prime is 109639. The next prime is 109661. The reversal of 109645 is 546901.

109645 is nontrivially palindromic in base 13.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 546901 = 487 ⋅1123.

It can be written as a sum of positive squares in 2 ways, for example, as 84681 + 24964 = 291^2 + 158^2 .

It is a cyclic number.

It is not a de Polignac number, because 109645 - 2⁷ = 109517 is a prime.

It is a super-3 number, since 3×109645³ = 3954465130533375, which contains 333 as substring.

109645 is a lucky number.

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, 10960 + ... + 10969.

It is an arithmetic number, because the mean of its divisors is an integer number (32895).

2¹⁰⁹⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

109645 is a deficient number, since it is larger than the sum of its proper divisors (21935).

109645 is an equidigital number, since it uses as much as digits as its factorization.

109645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21934.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 109645 is about 331.1268639057. The cubic root of 109645 is about 47.8625989600.

The spelling of 109645 in words is "one hundred nine thousand, six hundred forty-five".