16193519905 has 4 divisors (see below), whose sum is σ = 19432223892. Its totient is φ = 12954815920.

The previous prime is 16193519891. The next prime is 16193519917. The reversal of 16193519905 is 50991539161.

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 2220388641 + 13973131264 = 47121^2 + 118208^2 .

It is not a de Polignac number, because 16193519905 - 2⁹ = 16193519393 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1619351986 + ... + 1619351995.

It is an arithmetic number, because the mean of its divisors is an integer number (4858055973).

Almost surely, 2^16193519905 is an apocalyptic number.

It is an amenable number.

16193519905 is a deficient number, since it is larger than the sum of its proper divisors (3238703987).

16193519905 is an equidigital number, since it uses as much as digits as its factorization.

16193519905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3238703986.

The product of its (nonzero) digits is 328050, while the sum is 49.

The spelling of 16193519905 in words is "sixteen billion, one hundred ninety-three million, five hundred nineteen thousand, nine hundred five".