18534647643 has 4 divisors (see below), whose sum is σ = 24712863528. Its totient is φ = 12356431760.

The previous prime is 18534647617. The next prime is 18534647693. The reversal of 18534647643 is 34674643581.

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

It is a cyclic number.

It is not a de Polignac number, because 18534647643 - 2⁸ = 18534647387 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18534647693) 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, 3089107938 + ... + 3089107943.

It is an arithmetic number, because the mean of its divisors is an integer number (6178215882).

Almost surely, 2^18534647643 is an apocalyptic number.

18534647643 is a deficient number, since it is larger than the sum of its proper divisors (6178215885).

18534647643 is an equidigital number, since it uses as much as digits as its factorization.

18534647643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6178215884.

The product of its digits is 5806080, while the sum is 51.

The spelling of 18534647643 in words is "eighteen billion, five hundred thirty-four million, six hundred forty-seven thousand, six hundred forty-three".