243978 has 32 divisors (see below), whose sum is σ = 576384. Its totient is φ = 67392.

The previous prime is 243973. The next prime is 243989. The reversal of 243978 is 879342.

243978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243973) by changing a digit.

243978 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 15 ways as a sum of consecutive naturals, for example, 1476 + ... + 1632.

It is an arithmetic number, because the mean of its divisors is an integer number (18012).

2²⁴³⁹⁷⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 243978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (288192).

243978 is an abundant number, since it is smaller than the sum of its proper divisors (332406).

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

243978 is a wasteful number, since it uses less digits than its factorization.

243978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206.

The product of its digits is 12096, while the sum is 33.

The square root of 243978 is about 493.9412920581. The cubic root of 243978 is about 62.4861195842.

It can be divided in two parts, 243 and 978, that added together give a palindrome (1221).

The spelling of 243978 in words is "two hundred forty-three thousand, nine hundred seventy-eight".