491671 has 4 divisors (see below), whose sum is σ = 513072. Its totient is φ = 470272.

The previous prime is 491669. The next prime is 491677. The reversal of 491671 is 176194.

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 491671 - 2¹ = 491669 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 (491677) 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, 10666 + ... + 10711.

It is an arithmetic number, because the mean of its divisors is an integer number (128268).

2⁴⁹¹⁶⁷¹ is an apocalyptic number.

491671 is a deficient number, since it is larger than the sum of its proper divisors (21401).

491671 is a wasteful number, since it uses less digits than its factorization.

491671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21400.

The product of its digits is 1512, while the sum is 28.

The square root of 491671 is about 701.1925555794. The cubic root of 491671 is about 78.9268671055.

The spelling of 491671 in words is "four hundred ninety-one thousand, six hundred seventy-one".