686686523 has 2 divisors, whose sum is σ = 686686524. Its totient is φ = 686686522.

The previous prime is 686686519. The next prime is 686686541. The reversal of 686686523 is 325686686.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 686686523 - 2² = 686686519 is a prime.

It is not a weakly prime, because it can be changed into another prime (686686513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343343261 + 343343262.

It is an arithmetic number, because the mean of its divisors is an integer number (343343262).

Almost surely, 2^686686523 is an apocalyptic number.

686686523 is a deficient number, since it is larger than the sum of its proper divisors (1).

686686523 is an equidigital number, since it uses as much as digits as its factorization.

686686523 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2488320, while the sum is 50.

The square root of 686686523 is about 26204.7042150832. The cubic root of 686686523 is about 882.2388425447.

The spelling of 686686523 in words is "six hundred eighty-six million, six hundred eighty-six thousand, five hundred twenty-three".