242531 has 4 divisors (see below), whose sum is σ = 243672. Its totient is φ = 241392.

The previous prime is 242521. The next prime is 242533. The reversal of 242531 is 135242.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 242531 - 2⁶ = 242467 is a prime.

It is a super-2 number, since 2×242531² = 117642571922, which contains 22 as substring.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 242531.

It is not an unprimeable number, because it can be changed into a prime (242533) 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 in 3 ways as a sum of consecutive naturals, for example, 146 + ... + 711.

It is an arithmetic number, because the mean of its divisors is an integer number (60918).

2²⁴²⁵³¹ is an apocalyptic number.

242531 is a deficient number, since it is larger than the sum of its proper divisors (1141).

242531 is an equidigital number, since it uses as much as digits as its factorization.

242531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1140.

The product of its digits is 240, while the sum is 17.

The square root of 242531 is about 492.4743648151. The cubic root of 242531 is about 62.3623423619.

Adding to 242531 its reverse (135242), we get a palindrome (377773).

The spelling of 242531 in words is "two hundred forty-two thousand, five hundred thirty-one".