671731 has 4 divisors (see below), whose sum is σ = 681264. Its totient is φ = 662200.

The previous prime is 671729. The next prime is 671743. The reversal of 671731 is 137176.

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 671731 - 2¹ = 671729 is a prime.

It is a super-2 number, since 2×671731² = 902445072722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 671696 and 671705.

It is not an unprimeable number, because it can be changed into a prime (671701) 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, 4660 + ... + 4801.

It is an arithmetic number, because the mean of its divisors is an integer number (170316).

2⁶⁷¹⁷³¹ is an apocalyptic number.

671731 is a deficient number, since it is larger than the sum of its proper divisors (9533).

671731 is an equidigital number, since it uses as much as digits as its factorization.

671731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9532.

The product of its digits is 882, while the sum is 25.

The square root of 671731 is about 819.5919716542. The cubic root of 671731 is about 87.5786938307.

The spelling of 671731 in words is "six hundred seventy-one thousand, seven hundred thirty-one".