42191 has 4 divisors (see below), whose sum is σ = 43584. Its totient is φ = 40800.

The previous prime is 42187. The next prime is 42193. The reversal of 42191 is 19124.

It is a happy number.

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 42191 - 2² = 42187 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42193) 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, 650 + ... + 711.

It is an arithmetic number, because the mean of its divisors is an integer number (10896).

2⁴²¹⁹¹ is an apocalyptic number.

42191 is a deficient number, since it is larger than the sum of its proper divisors (1393).

42191 is a wasteful number, since it uses less digits than its factorization.

42191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1392.

The product of its digits is 72, while the sum is 17.

The square root of 42191 is about 205.4044790164. The cubic root of 42191 is about 34.8128789254.

It can be divided in two parts, 421 and 91, that added together give a 9-th power (512 = 2⁹).

The spelling of 42191 in words is "forty-two thousand, one hundred ninety-one".