686172212339 has 2 divisors, whose sum is σ = 686172212340. Its totient is φ = 686172212338.

The previous prime is 686172212311. The next prime is 686172212393. The reversal of 686172212339 is 933212271686.

686172212339 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (686172212393) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-686172212339 is a prime.

It is not a weakly prime, because it can be changed into another prime (686172212839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343086106169 + 343086106170.

It is an arithmetic number, because the mean of its divisors is an integer number (343086106170).

Almost surely, 2^686172212339 is an apocalyptic number.

686172212339 is a deficient number, since it is larger than the sum of its proper divisors (1).

686172212339 is an equidigital number, since it uses as much as digits as its factorization.

686172212339 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1306368, while the sum is 50.

The spelling of 686172212339 in words is "six hundred eighty-six billion, one hundred seventy-two million, two hundred twelve thousand, three hundred thirty-nine".