17938939 has 2 divisors, whose sum is σ = 17938940. Its totient is φ = 17938938.

The previous prime is 17938937. The next prime is 17938979. The reversal of 17938939 is 93983971.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 17938939 - 2¹ = 17938937 is a prime.

Together with 17938937, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 17938892 and 17938901.

It is not a weakly prime, because it can be changed into another prime (17938933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8969469 + 8969470.

It is an arithmetic number, because the mean of its divisors is an integer number (8969470).

Almost surely, 2^17938939 is an apocalyptic number.

17938939 is a deficient number, since it is larger than the sum of its proper divisors (1).

17938939 is an equidigital number, since it uses as much as digits as its factorization.

17938939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 367416, while the sum is 49.

The square root of 17938939 is about 4235.4384660859. The cubic root of 17938939 is about 261.7774609359. Note that the first 3 decimals are identical.

The spelling of 17938939 in words is "seventeen million, nine hundred thirty-eight thousand, nine hundred thirty-nine".