688204117 has 2 divisors, whose sum is σ = 688204118. Its totient is φ = 688204116.

The previous prime is 688204043. The next prime is 688204157. The reversal of 688204117 is 711402886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 669463876 + 18740241 = 25874^2 + 4329^2 .

It is a cyclic number.

It is not a de Polignac number, because 688204117 - 2¹¹ = 688202069 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688204157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344102058 + 344102059.

It is an arithmetic number, because the mean of its divisors is an integer number (344102059).

Almost surely, 2^688204117 is an apocalyptic number.

It is an amenable number.

688204117 is a deficient number, since it is larger than the sum of its proper divisors (1).

688204117 is an equidigital number, since it uses as much as digits as its factorization.

688204117 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 688204117 is about 26233.6447524929. The cubic root of 688204117 is about 882.8882874850. Note that the first 3 decimals are identical.

The spelling of 688204117 in words is "six hundred eighty-eight million, two hundred four thousand, one hundred seventeen".