18561444464 has 10 divisors (see below), whose sum is σ = 35962798680. Its totient is φ = 9280722224.

The previous prime is 18561444443. The next prime is 18561444479. The reversal of 18561444464 is 46444416581.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 580045124 + ... + 580045155.

It is an arithmetic number, because the mean of its divisors is an integer number (3596279868).

Almost surely, 2^18561444464 is an apocalyptic number.

It is an amenable number.

18561444464 is a deficient number, since it is larger than the sum of its proper divisors (17401354216).

18561444464 is a wasteful number, since it uses less digits than its factorization.

18561444464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1160090287 (or 1160090281 counting only the distinct ones).

The product of its digits is 1474560, while the sum is 47.

The spelling of 18561444464 in words is "eighteen billion, five hundred sixty-one million, four hundred forty-four thousand, four hundred sixty-four".