684481 has 12 divisors (see below), whose sum is σ = 812820. Its totient is φ = 574560.

The previous prime is 684473. The next prime is 684493. The reversal of 684481 is 184486.

It can be written as a sum of positive squares in 2 ways, for example, as 313600 + 370881 = 560^2 + 609^2 .

It is not a de Polignac number, because 684481 - 2³ = 684473 is a prime.

It is a super-2 number, since 2×684481² = 937028478722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (684451) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2875 + ... + 3103.

It is an arithmetic number, because the mean of its divisors is an integer number (67735).

2⁶⁸⁴⁴⁸¹ is an apocalyptic number.

684481 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

684481 is a deficient number, since it is larger than the sum of its proper divisors (128339).

684481 is a wasteful number, since it uses less digits than its factorization.

684481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304 (or 297 counting only the distinct ones).

The product of its digits is 6144, while the sum is 31.

The square root of 684481 is about 827.3336690840. Note that the first 3 decimals coincide. The cubic root of 684481 is about 88.1293294655.

The spelling of 684481 in words is "six hundred eighty-four thousand, four hundred eighty-one".