42591 has 4 divisors (see below), whose sum is σ = 56792. Its totient is φ = 28392.

The previous prime is 42589. The next prime is 42611. The reversal of 42591 is 19524.

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

It is not a de Polignac number, because 42591 - 2¹ = 42589 is a prime.

It is a D-number.

It is a Duffinian number.

42591 is a lucky number.

It is a plaindrome in base 11.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 42591.

It is not an unprimeable number, because it can be changed into a prime (42571) 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, 7096 + ... + 7101.

It is an arithmetic number, because the mean of its divisors is an integer number (14198).

2⁴²⁵⁹¹ is an apocalyptic number.

42591 is a deficient number, since it is larger than the sum of its proper divisors (14201).

42591 is a wasteful number, since it uses less digits than its factorization.

42591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14200.

The product of its digits is 360, while the sum is 21.

The square root of 42591 is about 206.3758706826. The cubic root of 42591 is about 34.9225498283.

The spelling of 42591 in words is "forty-two thousand, five hundred ninety-one".