17959117809 has 4 divisors (see below), whose sum is σ = 23945490416. Its totient is φ = 11972745204.

The previous prime is 17959117769. The next prime is 17959117859. The reversal of 17959117809 is 90871195971.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90871195971 = 3 ⋅30290398657.

It is not a de Polignac number, because 17959117809 - 2¹⁵ = 17959085041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (17959117859) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2993186299 + ... + 2993186304.

It is an arithmetic number, because the mean of its divisors is an integer number (5986372604).

Almost surely, 2^17959117809 is an apocalyptic number.

It is an amenable number.

17959117809 is a deficient number, since it is larger than the sum of its proper divisors (5986372607).

17959117809 is an equidigital number, since it uses as much as digits as its factorization.

17959117809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5986372606.

The product of its (nonzero) digits is 1428840, while the sum is 57.

The spelling of 17959117809 in words is "seventeen billion, nine hundred fifty-nine million, one hundred seventeen thousand, eight hundred nine".