17908728913 has 4 divisors (see below), whose sum is σ = 18039449700. Its totient is φ = 17778008128.

The previous prime is 17908728907. The next prime is 17908728917. The reversal of 17908728913 is 31982780971.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6970079169 + 10938649744 = 83487^2 + 104588^2 .

It is a cyclic number.

It is not a de Polignac number, because 17908728913 - 2¹⁷ = 17908597841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (17908728917) 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, 65360188 + ... + 65360461.

It is an arithmetic number, because the mean of its divisors is an integer number (4509862425).

Almost surely, 2^17908728913 is an apocalyptic number.

It is an amenable number.

17908728913 is a deficient number, since it is larger than the sum of its proper divisors (130720787).

17908728913 is a wasteful number, since it uses less digits than its factorization.

17908728913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130720786.

The product of its (nonzero) digits is 1524096, while the sum is 55.

The spelling of 17908728913 in words is "seventeen billion, nine hundred eight million, seven hundred twenty-eight thousand, nine hundred thirteen".