42336521 has 4 divisors (see below), whose sum is σ = 42376212. Its totient is φ = 42296832.

The previous prime is 42336509. The next prime is 42336527. The reversal of 42336521 is 12563324.

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 20611600 + 21724921 = 4540^2 + 4661^2 .

It is a cyclic number.

It is not a de Polignac number, because 42336521 - 2⁶ = 42336457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42336527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18200 + ... + 20393.

It is an arithmetic number, because the mean of its divisors is an integer number (10594053).

Almost surely, 2^42336521 is an apocalyptic number.

It is an amenable number.

42336521 is a deficient number, since it is larger than the sum of its proper divisors (39691).

42336521 is a wasteful number, since it uses less digits than its factorization.

42336521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39690.

The product of its digits is 4320, while the sum is 26.

The square root of 42336521 is about 6506.6520577022. The cubic root of 42336521 is about 348.5285737025.

Adding to 42336521 its reverse (12563324), we get a palindrome (54899845).

The spelling of 42336521 in words is "forty-two million, three hundred thirty-six thousand, five hundred twenty-one".