684004332509 has 2 divisors, whose sum is σ = 684004332510. Its totient is φ = 684004332508.

The previous prime is 684004332493. The next prime is 684004332521. The reversal of 684004332509 is 905233400486.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 683561861284 + 442471225 = 826778^2 + 21035^2 .

It is a cyclic number.

It is not a de Polignac number, because 684004332509 - 2⁴ = 684004332493 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 684004332509.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (684004332409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342002166254 + 342002166255.

It is an arithmetic number, because the mean of its divisors is an integer number (342002166255).

Almost surely, 2^684004332509 is an apocalyptic number.

It is an amenable number.

684004332509 is a deficient number, since it is larger than the sum of its proper divisors (1).

684004332509 is an equidigital number, since it uses as much as digits as its factorization.

684004332509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 622080, while the sum is 44.

The spelling of 684004332509 in words is "six hundred eighty-four billion, four million, three hundred thirty-two thousand, five hundred nine".