684109 has 2 divisors, whose sum is σ = 684110. Its totient is φ = 684108.

The previous prime is 684091. The next prime is 684113. The reversal of 684109 is 901486.

Together with previous prime (684091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 455625 + 228484 = 675^2 + 478^2 .

It is a cyclic number.

It is not a de Polignac number, because 684109 - 2⁹ = 683597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (684119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342054 + 342055.

It is an arithmetic number, because the mean of its divisors is an integer number (342055).

2⁶⁸⁴¹⁰⁹ is an apocalyptic number.

It is an amenable number.

684109 is a deficient number, since it is larger than the sum of its proper divisors (1).

684109 is an equidigital number, since it uses as much as digits as its factorization.

684109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 684109 is about 827.1088199264. The cubic root of 684109 is about 88.1133611375.

The spelling of 684109 in words is "six hundred eighty-four thousand, one hundred nine".