684987 has 8 divisors (see below), whose sum is σ = 935760. Its totient is φ = 445440.

The previous prime is 684977. The next prime is 684989. The reversal of 684987 is 789486.

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 684987 - 2⁶ = 684923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (684989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2662 + ... + 2907.

It is an arithmetic number, because the mean of its divisors is an integer number (116970).

2⁶⁸⁴⁹⁸⁷ is an apocalyptic number.

684987 is a deficient number, since it is larger than the sum of its proper divisors (250773).

684987 is a wasteful number, since it uses less digits than its factorization.

684987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5613.

The product of its digits is 96768, while the sum is 42.

The square root of 684987 is about 827.6394142379. The cubic root of 684987 is about 88.1510405414.

The spelling of 684987 in words is "six hundred eighty-four thousand, nine hundred eighty-seven".