19345809616618 has 4 divisors (see below), whose sum is σ = 29018714424930. Its totient is φ = 9672904808308.

The previous prime is 19345809616613. The next prime is 19345809616633. The reversal of 19345809616618 is 81661690854391.

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

It can be written as a sum of positive squares in only one way, i.e., 11295158123929 + 8050651492689 = 3360827^2 + 2837367^2 .

It is a Smith number, since the sum of its digits (67) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (19345809616613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4836452404153 + ... + 4836452404156.

Almost surely, 2^{19345809616618} is an apocalyptic number.

19345809616618 is a deficient number, since it is larger than the sum of its proper divisors (9672904808312).

19345809616618 is an equidigital number, since it uses as much as digits as its factorization.

19345809616618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9672904808311.

The product of its (nonzero) digits is 67184640, while the sum is 67.

The spelling of 19345809616618 in words is "nineteen trillion, three hundred forty-five billion, eight hundred nine million, six hundred sixteen thousand, six hundred eighteen".