17218939 has 2 divisors, whose sum is σ = 17218940. Its totient is φ = 17218938.

The previous prime is 17218937. The next prime is 17219003. The reversal of 17218939 is 93981271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 17218939 - 2¹ = 17218937 is a prime.

Together with 17218937, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (17218937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8609469 + 8609470.

It is an arithmetic number, because the mean of its divisors is an integer number (8609470).

Almost surely, 2^17218939 is an apocalyptic number.

17218939 is a deficient number, since it is larger than the sum of its proper divisors (1).

17218939 is an equidigital number, since it uses as much as digits as its factorization.

17218939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 40.

The square root of 17218939 is about 4149.5709416758. The cubic root of 17218939 is about 258.2272850419.

The spelling of 17218939 in words is "seventeen million, two hundred eighteen thousand, nine hundred thirty-nine".