688695017 has 2 divisors, whose sum is σ = 688695018. Its totient is φ = 688695016.

The previous prime is 688695011. The next prime is 688695031. The reversal of 688695017 is 710596886.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 633579241 + 55115776 = 25171^2 + 7424^2 .

It is a cyclic number.

It is not a de Polignac number, because 688695017 - 2⁸ = 688694761 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (688695011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344347508 + 344347509.

It is an arithmetic number, because the mean of its divisors is an integer number (344347509).

Almost surely, 2^688695017 is an apocalyptic number.

It is an amenable number.

688695017 is a deficient number, since it is larger than the sum of its proper divisors (1).

688695017 is an equidigital number, since it uses as much as digits as its factorization.

688695017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 725760, while the sum is 50.

The square root of 688695017 is about 26242.9993903136. Note that the first 3 decimals coincide. The cubic root of 688695017 is about 883.0981607088.

The spelling of 688695017 in words is "six hundred eighty-eight million, six hundred ninety-five thousand, seventeen".