42540231 has 4 divisors (see below), whose sum is σ = 56720312. Its totient is φ = 28360152.

The previous prime is 42540227. The next prime is 42540263. The reversal of 42540231 is 13204524.

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

It is not a de Polignac number, because 42540231 - 2² = 42540227 is a prime.

It is a super-2 number, since 2×42540231² = 3619342507066722, 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 = 42540198 and 42540207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42540331) 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, 7090036 + ... + 7090041.

It is an arithmetic number, because the mean of its divisors is an integer number (14180078).

Almost surely, 2^42540231 is an apocalyptic number.

42540231 is a deficient number, since it is larger than the sum of its proper divisors (14180081).

42540231 is a wasteful number, since it uses less digits than its factorization.

42540231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14180080.

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 42540231 is about 6522.2872521839. The cubic root of 42540231 is about 349.0866827374.

Adding to 42540231 its reverse (13204524), we get a palindrome (55744755).

The spelling of 42540231 in words is "forty-two million, five hundred forty thousand, two hundred thirty-one".