42431531 has 4 divisors (see below), whose sum is σ = 42474432. Its totient is φ = 42388632.

The previous prime is 42431461. The next prime is 42431533. The reversal of 42431531 is 13513424.

42431531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 42431531 - 2¹⁴ = 42415147 is a prime.

It is a super-2 number, since 2×42431531² = 3600869646007922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42431497 and 42431506.

It is not an unprimeable number, because it can be changed into a prime (42431533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19931 + ... + 21956.

It is an arithmetic number, because the mean of its divisors is an integer number (10618608).

Almost surely, 2^42431531 is an apocalyptic number.

42431531 is a deficient number, since it is larger than the sum of its proper divisors (42901).

42431531 is a wasteful number, since it uses less digits than its factorization.

42431531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42900.

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

The square root of 42431531 is about 6513.9489558946. The cubic root of 42431531 is about 348.7890970758.

Adding to 42431531 its reverse (13513424), we get a palindrome (55944955).

The spelling of 42431531 in words is "forty-two million, four hundred thirty-one thousand, five hundred thirty-one".