18683857 has 2 divisors, whose sum is σ = 18683858. Its totient is φ = 18683856.

The previous prime is 18683851. The next prime is 18683893. The reversal of 18683857 is 75838681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12453841 + 6230016 = 3529^2 + 2496^2 .

It is an emirp because it is prime and its reverse (75838681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18683857 - 2⁷ = 18683729 is a prime.

It is not a weakly prime, because it can be changed into another prime (18683851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9341928 + 9341929.

It is an arithmetic number, because the mean of its divisors is an integer number (9341929).

Almost surely, 2^18683857 is an apocalyptic number.

It is an amenable number.

18683857 is a deficient number, since it is larger than the sum of its proper divisors (1).

18683857 is an equidigital number, since it uses as much as digits as its factorization.

18683857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 322560, while the sum is 46.

The square root of 18683857 is about 4322.4827356509. The cubic root of 18683857 is about 265.3518856851.

The spelling of 18683857 in words is "eighteen million, six hundred eighty-three thousand, eight hundred fifty-seven".