18686837 has 6 divisors (see below), whose sum is σ = 20235042. Its totient is φ = 17249232.

The previous prime is 18686827. The next prime is 18686849. The reversal of 18686837 is 73868681.

It can be written as a sum of positive squares in 3 ways, for example, as 376996 + 18309841 = 614^2 + 4279^2 .

It is not a de Polignac number, because 18686837 - 2⁴ = 18686821 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18686791 and 18686800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18686807) 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 in 5 ways as a sum of consecutive naturals, for example, 55118 + ... + 55455.

It is an arithmetic number, because the mean of its divisors is an integer number (3372507).

Almost surely, 2^18686837 is an apocalyptic number.

It is an amenable number.

18686837 is a deficient number, since it is larger than the sum of its proper divisors (1548205).

18686837 is a wasteful number, since it uses less digits than its factorization.

18686837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110599 (or 110586 counting only the distinct ones).

The product of its digits is 387072, while the sum is 47.

The square root of 18686837 is about 4322.8274312075. The cubic root of 18686837 is about 265.3659924545.

The spelling of 18686837 in words is "eighteen million, six hundred eighty-six thousand, eight hundred thirty-seven".