42591181 has 4 divisors (see below), whose sum is σ = 43742332. Its totient is φ = 41440032.

The previous prime is 42591083. The next prime is 42591187. The reversal of 42591181 is 18119524.

It is a happy number.

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 20884900 + 21706281 = 4570^2 + 4659^2 .

It is a cyclic number.

It is not a de Polignac number, because 42591181 - 2¹⁷ = 42460109 is a prime.

It is a super-2 number, since 2×42591181² = 3628017397949522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42591187) 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, 575520 + ... + 575593.

It is an arithmetic number, because the mean of its divisors is an integer number (10935583).

Almost surely, 2^42591181 is an apocalyptic number.

It is an amenable number.

42591181 is a deficient number, since it is larger than the sum of its proper divisors (1151151).

42591181 is a wasteful number, since it uses less digits than its factorization.

42591181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1151150.

The product of its digits is 2880, while the sum is 31.

The square root of 42591181 is about 6526.1919217872. The cubic root of 42591181 is about 349.2259929864.

The spelling of 42591181 in words is "forty-two million, five hundred ninety-one thousand, one hundred eighty-one".