686958197 has 2 divisors, whose sum is σ = 686958198. Its totient is φ = 686958196.

The previous prime is 686958187. The next prime is 686958199. The reversal of 686958197 is 791859686.

686958197 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 627452401 + 59505796 = 25049^2 + 7714^2 .

It is a cyclic number.

It is not a de Polignac number, because 686958197 - 2⁶ = 686958133 is a prime.

Together with 686958199, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (686958199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343479098 + 343479099.

It is an arithmetic number, because the mean of its divisors is an integer number (343479099).

Almost surely, 2^686958197 is an apocalyptic number.

It is an amenable number.

686958197 is a deficient number, since it is larger than the sum of its proper divisors (1).

686958197 is an equidigital number, since it uses as much as digits as its factorization.

686958197 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6531840, while the sum is 59.

The square root of 686958197 is about 26209.8873900671. The cubic root of 686958197 is about 882.3551740127.

The spelling of 686958197 in words is "six hundred eighty-six million, nine hundred fifty-eight thousand, one hundred ninety-seven".