42542421 has 8 divisors (see below), whose sum is σ = 57037344. Its totient is φ = 28204560.

The previous prime is 42542417. The next prime is 42542431. The reversal of 42542421 is 12424524.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42542421 - 2² = 42542417 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 42542391 and 42542400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42542431) 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 7 ways as a sum of consecutive naturals, for example, 38631 + ... + 39716.

It is an arithmetic number, because the mean of its divisors is an integer number (7129668).

Almost surely, 2^42542421 is an apocalyptic number.

It is an amenable number.

42542421 is a deficient number, since it is larger than the sum of its proper divisors (14494923).

42542421 is a wasteful number, since it uses less digits than its factorization.

42542421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78531.

The product of its digits is 2560, while the sum is 24.

The square root of 42542421 is about 6522.4551359132. The cubic root of 42542421 is about 349.0926730412.

Adding to 42542421 its reverse (12424524), we get a palindrome (54966945).

The spelling of 42542421 in words is "forty-two million, five hundred forty-two thousand, four hundred twenty-one".