243564 has 12 divisors (see below), whose sum is σ = 568344. Its totient is φ = 81184.

The previous prime is 243553. The next prime is 243577. The reversal of 243564 is 465342.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

243564 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10137 + ... + 10160.

It is an arithmetic number, because the mean of its divisors is an integer number (47362).

2²⁴³⁵⁶⁴ is an apocalyptic number.

It is an amenable number.

243564 is an abundant number, since it is smaller than the sum of its proper divisors (324780).

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

243564 is a wasteful number, since it uses less digits than its factorization.

243564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20304 (or 20302 counting only the distinct ones).

The product of its digits is 2880, while the sum is 24.

The square root of 243564 is about 493.5220359822. The cubic root of 243564 is about 62.4507558771.

The spelling of 243564 in words is "two hundred forty-three thousand, five hundred sixty-four".