688485191 has 2 divisors, whose sum is σ = 688485192. Its totient is φ = 688485190.

The previous prime is 688485179. The next prime is 688485241. The reversal of 688485191 is 191584886.

It is an a-pointer prime, because the next prime (688485241) can be obtained adding 688485191 to its sum of digits (50).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-688485191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688485991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344242595 + 344242596.

It is an arithmetic number, because the mean of its divisors is an integer number (344242596).

Almost surely, 2^688485191 is an apocalyptic number.

688485191 is a deficient number, since it is larger than the sum of its proper divisors (1).

688485191 is an equidigital number, since it uses as much as digits as its factorization.

688485191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 552960, while the sum is 50.

The square root of 688485191 is about 26239.0013338923. The cubic root of 688485191 is about 883.0084665425.

The spelling of 688485191 in words is "six hundred eighty-eight million, four hundred eighty-five thousand, one hundred ninety-one".