42431321 has 4 divisors (see below), whose sum is σ = 43894500. Its totient is φ = 40968144.

The previous prime is 42431317. The next prime is 42431357. The reversal of 42431321 is 12313424.

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 27415696 + 15015625 = 5236^2 + 3875^2 .

It is a cyclic number.

It is not a de Polignac number, because 42431321 - 2² = 42431317 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 42431293 and 42431302.

It is not an unprimeable number, because it can be changed into a prime (42434321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 731546 + ... + 731603.

It is an arithmetic number, because the mean of its divisors is an integer number (10973625).

Almost surely, 2^42431321 is an apocalyptic number.

It is an amenable number.

42431321 is a deficient number, since it is larger than the sum of its proper divisors (1463179).

42431321 is a wasteful number, since it uses less digits than its factorization.

42431321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1463178.

The product of its digits is 576, while the sum is 20.

The square root of 42431321 is about 6513.9328366203. The cubic root of 42431321 is about 348.7885216717.

Adding to 42431321 its reverse (12313424), we get a palindrome (54744745).

The spelling of 42431321 in words is "forty-two million, four hundred thirty-one thousand, three hundred twenty-one".