18048028561 has 4 divisors (see below), whose sum is σ = 18053489392. Its totient is φ = 18042567732.

The previous prime is 18048028543. The next prime is 18048028613. The reversal of 18048028561 is 16582084081.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18048028561 - 2⁹ = 18048028049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18048028501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2725455 + ... + 2732068.

It is an arithmetic number, because the mean of its divisors is an integer number (4513372348).

Almost surely, 2^18048028561 is an apocalyptic number.

It is an amenable number.

18048028561 is a deficient number, since it is larger than the sum of its proper divisors (5460831).

18048028561 is an equidigital number, since it uses as much as digits as its factorization.

18048028561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5460830.

The product of its (nonzero) digits is 122880, while the sum is 43.

The spelling of 18048028561 in words is "eighteen billion, forty-eight million, twenty-eight thousand, five hundred sixty-one".