688242617 has 2 divisors, whose sum is σ = 688242618. Its totient is φ = 688242616.

The previous prime is 688242553. The next prime is 688242619. The reversal of 688242617 is 716242886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 512388496 + 175854121 = 22636^2 + 13261^2 .

It is a cyclic number.

It is not a de Polignac number, because 688242617 - 2⁶ = 688242553 is a prime.

Together with 688242619, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (688242619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344121308 + 344121309.

It is an arithmetic number, because the mean of its divisors is an integer number (344121309).

Almost surely, 2^688242617 is an apocalyptic number.

It is an amenable number.

688242617 is a deficient number, since it is larger than the sum of its proper divisors (1).

688242617 is an equidigital number, since it uses as much as digits as its factorization.

688242617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 258048, while the sum is 44.

The square root of 688242617 is about 26234.3785327574. The cubic root of 688242617 is about 882.9047508977.

The spelling of 688242617 in words is "six hundred eighty-eight million, two hundred forty-two thousand, six hundred seventeen".