18540744463 has 4 divisors (see below), whose sum is σ = 18546123600. Its totient is φ = 18535365328.

The previous prime is 18540744449. The next prime is 18540744479. The reversal of 18540744463 is 36444704581.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36444704581 = 199 ⋅183139219.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18540744463 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18540744403) by changing a digit.

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, 2684395 + ... + 2691292.

It is an arithmetic number, because the mean of its divisors is an integer number (4636530900).

Almost surely, 2^18540744463 is an apocalyptic number.

18540744463 is a deficient number, since it is larger than the sum of its proper divisors (5379137).

18540744463 is an equidigital number, since it uses as much as digits as its factorization.

18540744463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5379136.

The product of its (nonzero) digits is 1290240, while the sum is 46.

The spelling of 18540744463 in words is "eighteen billion, five hundred forty million, seven hundred forty-four thousand, four hundred sixty-three".