18049322551 has 4 divisors (see below), whose sum is σ = 19437731992. Its totient is φ = 16660913112.

The previous prime is 18049322549. The next prime is 18049322563. The reversal of 18049322551 is 15522394081.

It is a happy number.

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 18049322551 - 2¹ = 18049322549 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 (18049322531) 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, 694204701 + ... + 694204726.

It is an arithmetic number, because the mean of its divisors is an integer number (4859432998).

Almost surely, 2^18049322551 is an apocalyptic number.

18049322551 is a deficient number, since it is larger than the sum of its proper divisors (1388409441).

18049322551 is a wasteful number, since it uses less digits than its factorization.

18049322551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1388409440.

The product of its (nonzero) digits is 86400, while the sum is 40.

The spelling of 18049322551 in words is "eighteen billion, forty-nine million, three hundred twenty-two thousand, five hundred fifty-one".