684943 has 4 divisors (see below), whose sum is σ = 782800. Its totient is φ = 587088.

The previous prime is 684923. The next prime is 684949. The reversal of 684943 is 349486.

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 684943 - 2¹³ = 676751 is a prime.

It is a Duffinian number.

684943 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 684899 and 684908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (684949) 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, 48918 + ... + 48931.

It is an arithmetic number, because the mean of its divisors is an integer number (195700).

2⁶⁸⁴⁹⁴³ is an apocalyptic number.

684943 is a deficient number, since it is larger than the sum of its proper divisors (97857).

684943 is an equidigital number, since it uses as much as digits as its factorization.

684943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97856.

The product of its digits is 20736, while the sum is 34.

The square root of 684943 is about 827.6128321866. The cubic root of 684943 is about 88.1491530463.

The spelling of 684943 in words is "six hundred eighty-four thousand, nine hundred forty-three".