105609 has 16 divisors (see below), whose sum is σ = 165888. Its totient is φ = 58512.

The previous prime is 105607. The next prime is 105613. The reversal of 105609 is 906501.

It is not a de Polignac number, because 105609 - 2¹ = 105607 is a prime.

It is a super-2 number, since 2×105609² = 22306521762, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (105601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 934 + ... + 1040.

It is an arithmetic number, because the mean of its divisors is an integer number (10368).

2¹⁰⁵⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

105609 is a deficient number, since it is larger than the sum of its proper divisors (60279).

105609 is a wasteful number, since it uses less digits than its factorization.

105609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164.

The product of its (nonzero) digits is 270, while the sum is 21.

The square root of 105609 is about 324.9753836831. The cubic root of 105609 is about 47.2679727825.

The spelling of 105609 in words is "one hundred five thousand, six hundred nine".