684871 has 8 divisors (see below), whose sum is σ = 779904. Its totient is φ = 595320.

The previous prime is 684869. The next prime is 684889. The reversal of 684871 is 178486.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 684871 - 2¹ = 684869 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 (684841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1101 + ... + 1606.

It is an arithmetic number, because the mean of its divisors is an integer number (97488).

2⁶⁸⁴⁸⁷¹ is an apocalyptic number.

684871 is a deficient number, since it is larger than the sum of its proper divisors (95033).

684871 is a wasteful number, since it uses less digits than its factorization.

684871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2741.

The product of its digits is 10752, while the sum is 34.

The square root of 684871 is about 827.5693324429. The cubic root of 684871 is about 88.1460642436.

The spelling of 684871 in words is "six hundred eighty-four thousand, eight hundred seventy-one".