18718929505 has 4 divisors (see below), whose sum is σ = 22462715412. Its totient is φ = 14975143600.

The previous prime is 18718929499. The next prime is 18718929511. The reversal of 18718929505 is 50592981781.

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

It is an interprime number because it is at equal distance from previous prime (18718929499) and next prime (18718929511).

It can be written as a sum of positive squares in 2 ways, for example, as 5859596304 + 12859333201 = 76548^2 + 113399^2 .

It is not a de Polignac number, because 18718929505 - 2¹³ = 18718921313 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1871892946 + ... + 1871892955.

It is an arithmetic number, because the mean of its divisors is an integer number (5615678853).

Almost surely, 2^18718929505 is an apocalyptic number.

It is an amenable number.

18718929505 is a deficient number, since it is larger than the sum of its proper divisors (3743785907).

18718929505 is an equidigital number, since it uses as much as digits as its factorization.

18718929505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3743785906.

The product of its (nonzero) digits is 1814400, while the sum is 55.

The spelling of 18718929505 in words is "eighteen billion, seven hundred eighteen million, nine hundred twenty-nine thousand, five hundred five".