243138 has 24 divisors (see below), whose sum is σ = 566352. Its totient is φ = 69384.

The previous prime is 243137. The next prime is 243149. The reversal of 243138 is 831342.

It is a happy number.

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

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 243138.

It is not an unprimeable number, because it can be changed into a prime (243137) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 120 + ... + 707.

It is an arithmetic number, because the mean of its divisors is an integer number (23598).

2²⁴³¹³⁸ is an apocalyptic number.

243138 is an abundant number, since it is smaller than the sum of its proper divisors (323214).

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

243138 is a wasteful number, since it uses less digits than its factorization.

243138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 846 (or 839 counting only the distinct ones).

The product of its digits is 576, while the sum is 21.

The square root of 243138 is about 493.0902554300. The cubic root of 243138 is about 62.4143252778.

The spelling of 243138 in words is "two hundred forty-three thousand, one hundred thirty-eight".