42542321 has 4 divisors (see below), whose sum is σ = 42557172. Its totient is φ = 42527472.

The previous prime is 42542303. The next prime is 42542329. The reversal of 42542321 is 12324524.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17181025 + 25361296 = 4145^2 + 5036^2 .

It is a cyclic number.

It is not a de Polignac number, because 42542321 - 2¹⁸ = 42280177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42542329) 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, 1610 + ... + 9363.

It is an arithmetic number, because the mean of its divisors is an integer number (10639293).

Almost surely, 2^42542321 is an apocalyptic number.

It is an amenable number.

42542321 is a deficient number, since it is larger than the sum of its proper divisors (14851).

42542321 is a wasteful number, since it uses less digits than its factorization.

42542321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14850.

The product of its digits is 1920, while the sum is 23.

The square root of 42542321 is about 6522.4474700836. The cubic root of 42542321 is about 349.0923995158.

Adding to 42542321 its reverse (12324524), we get a palindrome (54866845).

The spelling of 42542321 in words is "forty-two million, five hundred forty-two thousand, three hundred twenty-one".