243556 has 6 divisors (see below), whose sum is σ = 426230. Its totient is φ = 121776.

The previous prime is 243553. The next prime is 243577. The reversal of 243556 is 655342.

243556 = 89² + 90² + ... + 112².

It can be written as a sum of positive squares in only one way, i.e., 147456 + 96100 = 384^2 + 310^2 .

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 243556.

It is not an unprimeable number, because it can be changed into a prime (243553) by changing a digit.

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 as a sum of consecutive naturals, namely, 30441 + ... + 30448.

2²⁴³⁵⁵⁶ is an apocalyptic number.

It is an amenable number.

243556 is a deficient number, since it is larger than the sum of its proper divisors (182674).

243556 is a wasteful number, since it uses less digits than its factorization.

243556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60893 (or 60891 counting only the distinct ones).

The product of its digits is 3600, while the sum is 25.

The square root of 243556 is about 493.5139309077. The cubic root of 243556 is about 62.4500721259.

Adding to 243556 its reverse (655342), we get a palindrome (898898).

The spelling of 243556 in words is "two hundred forty-three thousand, five hundred fifty-six".