42531431 has 2 divisors, whose sum is σ = 42531432. Its totient is φ = 42531430.

The previous prime is 42531413. The next prime is 42531451. The reversal of 42531431 is 13413524.

Together with previous prime (42531413) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 42531431 - 2¹⁸ = 42269287 is a prime.

It is a super-2 number, since 2×42531431² = 3617845245815522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 42531397 and 42531406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42531451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21265715 + 21265716.

It is an arithmetic number, because the mean of its divisors is an integer number (21265716).

Almost surely, 2^42531431 is an apocalyptic number.

42531431 is a deficient number, since it is larger than the sum of its proper divisors (1).

42531431 is an equidigital number, since it uses as much as digits as its factorization.

42531431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 23.

The square root of 42531431 is about 6521.6126073234. The cubic root of 42531431 is about 349.0626100374.

Adding to 42531431 its reverse (13413524), we get a palindrome (55944955).

The spelling of 42531431 in words is "forty-two million, five hundred thirty-one thousand, four hundred thirty-one".