471991 has 4 divisors (see below), whose sum is σ = 508312. Its totient is φ = 435672.

The previous prime is 471959. The next prime is 471997. The reversal of 471991 is 199174.

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 471991 - 2⁵ = 471959 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 (471997) 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, 18141 + ... + 18166.

It is an arithmetic number, because the mean of its divisors is an integer number (127078).

2⁴⁷¹⁹⁹¹ is an apocalyptic number.

471991 is a deficient number, since it is larger than the sum of its proper divisors (36321).

471991 is a wasteful number, since it uses less digits than its factorization.

471991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36320.

The product of its digits is 2268, while the sum is 31.

The square root of 471991 is about 687.0160114582. The cubic root of 471991 is about 77.8594334419.

The spelling of 471991 in words is "four hundred seventy-one thousand, nine hundred ninety-one".