684971 has 8 divisors (see below), whose sum is σ = 799200. Its totient is φ = 586824.

The previous prime is 684961. The next prime is 684973. The reversal of 684971 is 179486.

It is not a de Polignac number, because 684971 - 2¹⁸ = 422827 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 7.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 684971.

It is not an unprimeable number, because it can be changed into a prime (684973) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 656 + ... + 1341.

It is an arithmetic number, because the mean of its divisors is an integer number (99900).

2⁶⁸⁴⁹⁷¹ is an apocalyptic number.

684971 is a deficient number, since it is larger than the sum of its proper divisors (114229).

684971 is an equidigital number, since it uses as much as digits as its factorization.

684971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2018 (or 2004 counting only the distinct ones).

The product of its digits is 12096, while the sum is 35.

The square root of 684971 is about 827.6297481362. The cubic root of 684971 is about 88.1503541889.

The spelling of 684971 in words is "six hundred eighty-four thousand, nine hundred seventy-one".