686798659 has 2 divisors, whose sum is σ = 686798660. Its totient is φ = 686798658.

The previous prime is 686798621. The next prime is 686798669. The reversal of 686798659 is 956897686.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 686798659 - 2⁷ = 686798531 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 686798659.

It is not a weakly prime, because it can be changed into another prime (686798669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343399329 + 343399330.

It is an arithmetic number, because the mean of its divisors is an integer number (343399330).

Almost surely, 2^686798659 is an apocalyptic number.

686798659 is a deficient number, since it is larger than the sum of its proper divisors (1).

686798659 is an equidigital number, since it uses as much as digits as its factorization.

686798659 is an evil number, because the sum of its binary digits is even.

The product of its digits is 39191040, while the sum is 64.

The square root of 686798659 is about 26206.8437435720. The cubic root of 686798659 is about 882.2868631708.

The spelling of 686798659 in words is "six hundred eighty-six million, seven hundred ninety-eight thousand, six hundred fifty-nine".