243656 has 32 divisors (see below), whose sum is σ = 552000. Its totient is φ = 98496.

The previous prime is 243647. The next prime is 243671. The reversal of 243656 is 656342.

It is a d-powerful number, because it can be written as 2⁷ + 4⁷ + 6³ + 3¹¹ + 5⁵ + 6⁶ .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 950 + ... + 1178.

It is an arithmetic number, because the mean of its divisors is an integer number (17250).

2²⁴³⁶⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 243656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276000).

243656 is an abundant number, since it is smaller than the sum of its proper divisors (308344).

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

243656 is a wasteful number, since it uses less digits than its factorization.

243656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261 (or 257 counting only the distinct ones).

The product of its digits is 4320, while the sum is 26.

The square root of 243656 is about 493.6152347730. The cubic root of 243656 is about 62.4586179398.

Adding to 243656 its reverse (656342), we get a palindrome (899998).

Subtracting 243656 from its reverse (656342), we obtain a triangular number (412686 = T₉₀₈).

The spelling of 243656 in words is "two hundred forty-three thousand, six hundred fifty-six".