18049552561 has 8 divisors (see below), whose sum is σ = 18636307200. Its totient is φ = 17463079920.

The previous prime is 18049552559. The next prime is 18049552597. The reversal of 18049552561 is 16525594081.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18049552561 - 2¹ = 18049552559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18049552501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63675 + ... + 200383.

It is an arithmetic number, because the mean of its divisors is an integer number (2329538400).

Almost surely, 2^18049552561 is an apocalyptic number.

It is an amenable number.

18049552561 is a deficient number, since it is larger than the sum of its proper divisors (586754639).

18049552561 is a wasteful number, since it uses less digits than its factorization.

18049552561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140999.

The product of its (nonzero) digits is 432000, while the sum is 46.

The spelling of 18049552561 in words is "eighteen billion, forty-nine million, five hundred fifty-two thousand, five hundred sixty-one".