685804319 has 2 divisors, whose sum is σ = 685804320. Its totient is φ = 685804318.

The previous prime is 685804303. The next prime is 685804321. The reversal of 685804319 is 913408586.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 685804319 - 2⁴ = 685804303 is a prime.

It is a super-2 number, since 2×685804319² = 940655127918107522, which contains 22 as substring.

Together with 685804321, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 685804319.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (685804219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342902159 + 342902160.

It is an arithmetic number, because the mean of its divisors is an integer number (342902160).

Almost surely, 2^685804319 is an apocalyptic number.

685804319 is a deficient number, since it is larger than the sum of its proper divisors (1).

685804319 is an equidigital number, since it uses as much as digits as its factorization.

685804319 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 207360, while the sum is 44.

The square root of 685804319 is about 26187.8658733391. The cubic root of 685804319 is about 881.8608689207.

The spelling of 685804319 in words is "six hundred eighty-five million, eight hundred four thousand, three hundred nineteen".