18550551717 has 18 divisors (see below), whose sum is σ = 27824423718. Its totient is φ = 12367030104.

The previous prime is 18550551707. The next prime is 18550551737. The reversal of 18550551717 is 71715505581.

18550551717 is a `hidden beast` number, since 1 + 85 + 5 + 0 + 551 + 7 + 17 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16817161761 + 1733389956 = 129681^2 + 41634^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18550551717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18550551707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1407138 + ... + 1420259.

Almost surely, 2^18550551717 is an apocalyptic number.

It is an amenable number.

18550551717 is a deficient number, since it is larger than the sum of its proper divisors (9273872001).

18550551717 is an frugal number, since it uses more digits than its factorization.

18550551717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2827421 (or 2827400 counting only the distinct ones).

The product of its (nonzero) digits is 245000, while the sum is 45.

The spelling of 18550551717 in words is "eighteen billion, five hundred fifty million, five hundred fifty-one thousand, seven hundred seventeen".