18739937 has 2 divisors, whose sum is σ = 18739938. Its totient is φ = 18739936.

The previous prime is 18739907. The next prime is 18739939. The reversal of 18739937 is 73993781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10764961 + 7974976 = 3281^2 + 2824^2 .

It is an emirp because it is prime and its reverse (73993781) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18739937 - 2¹⁶ = 18674401 is a prime.

Together with 18739939, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18739891 and 18739900.

It is not a weakly prime, because it can be changed into another prime (18739939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9369968 + 9369969.

It is an arithmetic number, because the mean of its divisors is an integer number (9369969).

Almost surely, 2^18739937 is an apocalyptic number.

It is an amenable number.

18739937 is a deficient number, since it is larger than the sum of its proper divisors (1).

18739937 is an equidigital number, since it uses as much as digits as its factorization.

18739937 is an evil number, because the sum of its binary digits is even.

The product of its digits is 285768, while the sum is 47.

The square root of 18739937 is about 4328.9648878225. The cubic root of 18739937 is about 265.6171069765.

The spelling of 18739937 in words is "eighteen million, seven hundred thirty-nine thousand, nine hundred thirty-seven".