42031221 has 4 divisors (see below), whose sum is σ = 56041632. Its totient is φ = 28020812.

The previous prime is 42031201. The next prime is 42031243. The reversal of 42031221 is 12213024.

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 a cyclic number.

It is not a de Polignac number, because 42031221 - 2¹¹ = 42029173 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42031221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42031201) 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, 7005201 + ... + 7005206.

It is an arithmetic number, because the mean of its divisors is an integer number (14010408).

Almost surely, 2^42031221 is an apocalyptic number.

It is an amenable number.

42031221 is a deficient number, since it is larger than the sum of its proper divisors (14010411).

42031221 is a wasteful number, since it uses less digits than its factorization.

42031221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14010410.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 42031221 is about 6483.1490033779. The cubic root of 42031221 is about 347.6887741299.

Adding to 42031221 its reverse (12213024), we get a palindrome (54244245).

The spelling of 42031221 in words is "forty-two million, thirty-one thousand, two hundred twenty-one".