243642 has 16 divisors (see below), whose sum is σ = 556992. Its totient is φ = 69600.

The previous prime is 243631. The next prime is 243643. The reversal of 243642 is 246342.

It is a super-2 number, since 2×243642² = 118722848328, which contains 22 as substring.

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 243642.

It is not an unprimeable number, because it can be changed into a prime (243643) by changing a digit.

243642 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2859 + ... + 2942.

It is an arithmetic number, because the mean of its divisors is an integer number (34812).

2²⁴³⁶⁴² is an apocalyptic number.

243642 is an abundant number, since it is smaller than the sum of its proper divisors (313350).

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

243642 is a wasteful number, since it uses less digits than its factorization.

243642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5813.

The product of its digits is 1152, while the sum is 21.

The square root of 243642 is about 493.6010534835. The cubic root of 243642 is about 62.4574216666.

Adding to 243642 its reverse (246342), we get a palindrome (489984).

The spelling of 243642 in words is "two hundred forty-three thousand, six hundred forty-two".