242557 has 4 divisors (see below), whose sum is σ = 277216. Its totient is φ = 207900.

The previous prime is 242551. The next prime is 242591. The reversal of 242557 is 755242.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 242557 - 2¹¹ = 240509 is a prime.

It is the 493-rd Hogben number.

It is a pancake number, because a pancake can be divided into 242557 parts by 696 straight cuts.

It is a Duffinian number.

It is a nialpdrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242551) by changing a digit.

It is a nontrivial repunit in base 492.

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 3 ways as a sum of consecutive naturals, for example, 17319 + ... + 17332.

It is an arithmetic number, because the mean of its divisors is an integer number (69304).

2²⁴²⁵⁵⁷ is an apocalyptic number.

It is an amenable number.

242557 is a deficient number, since it is larger than the sum of its proper divisors (34659).

242557 is an equidigital number, since it uses as much as digits as its factorization.

242557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34658.

The product of its digits is 2800, while the sum is 25.

The square root of 242557 is about 492.5007614207. The cubic root of 242557 is about 62.3645707547.

Adding to 242557 its reverse (755242), we get a palindrome (997799).

The spelling of 242557 in words is "two hundred forty-two thousand, five hundred fifty-seven".